Business Segments and Customer Information - Geographic Area (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Revenues from External Customers and Long-Lived Assets [Line Items] | |||||||||||
| Revenues | $ 180,996 | $ 168,931 | $ 170,394 | $ 176,897 | $ 194,795 | $ 174,164 | $ 193,860 | $ 197,294 | $ 697,218 | $ 760,113 | $ 691,790 |
| United States | |||||||||||
| Revenues from External Customers and Long-Lived Assets [Line Items] | |||||||||||
| Revenues | 647,168 | 708,474 | 638,726 | ||||||||
| Other Countries | |||||||||||
| Revenues from External Customers and Long-Lived Assets [Line Items] | |||||||||||
| Revenues | $ 50,050 | $ 51,639 | $ 53,064 | ||||||||
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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