Consolidated Statements of Comprehensive Income - USD ($) $ 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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| Statement of Comprehensive Income [Abstract] | |||||||||||
| Net earnings | $ 2,438 | $ 7,669 | $ 6,454 | $ 10,363 | $ 7,392 | $ 17,249 | $ 13,368 | $ (5,321) | $ 26,924 | $ 32,688 | $ 58,956 |
| Net unrealized (loss) gain on short-term investments | (641) | (285) | 44 | ||||||||
| Other unrealized gain (loss) | 24 | (24) | |||||||||
| Changes in pension plan assets and benefit obligations | 7 | 17 | (2) | ||||||||
| Tax impact of the above-listed adjustments | 254 | 105 | (15) | ||||||||
| Total comprehensive income | $ 26,568 | $ 32,501 | $ 58,983 | ||||||||
| X | ||||||||||
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- 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 Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of tax expense (benefit) allocated to other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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