Selected Quarterly Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2014 |
Sep. 30, 2014 |
Jun. 30, 2014 |
Mar. 31, 2014 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Selected Quarterly Data (Unaudited) [Abstract] | |||||||||||
| Revenues | $ 144,669 | $ 137,396 | $ 131,126 | $ 120,791 | $ 94,951 | $ 101,749 | $ 107,962 | $ 119,409 | $ 533,982 | $ 424,071 | $ 471,638 |
| Contract costs | 128,883 | 123,652 | 118,672 | 108,948 | 85,521 | 93,388 | 96,481 | 107,611 | 480,155 | 383,001 | 424,250 |
| Operating income | 15,116 | 13,243 | 11,496 | 10,684 | 7,687 | 7,183 | 10,703 | 11,357 | 50,539 | 36,930 | 44,103 |
| Income from continuing operations | 7,745 | 6,474 | 5,479 | 5,220 | 4,389 | 3,887 | 5,944 | 6,269 | 24,918 | 20,489 | 23,990 |
| Loss from discontinued operations | (226) | (4) | (279) | (615) | 0 | (1,124) | (1,138) | ||||
| Net income | $ 7,745 | $ 6,474 | $ 5,479 | $ 5,220 | $ 4,163 | $ 3,883 | $ 5,665 | $ 5,654 | $ 24,918 | $ 19,365 | $ 22,852 |
| Basic earnings per share [Abstract] | |||||||||||
| Income from continuing operations (in dollars per share) | $ 1.44 | $ 1.20 | $ 1.02 | $ 0.97 | $ 0.82 | $ 0.73 | $ 1.11 | $ 1.17 | $ 4.64 | $ 3.83 | $ 4.50 |
| Loss from discontinued operations (in dollars per share) | (0.04) | 0 | (0.05) | (0.12) | 0 | (0.21) | (0.21) | ||||
| Net income (in dollars per share) | $ 1.44 | $ 1.20 | $ 1.02 | $ 0.97 | $ 0.78 | $ 0.73 | $ 1.06 | $ 1.05 | $ 4.64 | $ 3.62 | $ 4.29 |
| Basic weighted average shares outstanding (in shares) | 5,375,000 | 5,375,000 | 5,375,000 | 5,370,000 | 5,356,000 | 5,356,000 | 5,356,000 | 5,347,000 | 5,373,613 | 5,353,912 | 5,329,208 |
| Diluted earnings per share [Abstract] | |||||||||||
| Income from continuing operations (in dollars per share) | $ 1.43 | $ 1.20 | $ 1.02 | $ 0.97 | $ 0.82 | $ 0.72 | $ 1.11 | $ 1.17 | $ 4.62 | $ 3.82 | $ 4.49 |
| Loss from discontinued operations (in dollars per share) | (0.04) | 0 | (0.05) | (0.12) | 0 | (0.21) | (0.21) | ||||
| Net income (in dollars per share) | $ 1.43 | $ 1.20 | $ 1.02 | $ 0.97 | $ 0.78 | $ 0.72 | $ 1.06 | $ 1.05 | $ 4.62 | $ 3.61 | $ 4.28 |
| Diluted weighted average shares outstanding (in shares) | 5,407,000 | 5,396,000 | 5,391,000 | 5,380,000 | 5,380,000 | 5,372,000 | 5,368,000 | 5,364,000 | 5,393,635 | 5,371,200 | 5,343,267 |
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- Definition Costs incurred and are directly related to generating contract revenues. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- References No definition available.
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- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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