CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 71,563	$ 51,413	$ 110,758	$ 93,984
Other comprehensive income (loss), net of tax:
Fair value adjustment on interest rate swap contracts	0	0	0	187
Unealized gain on available-for-sale investments	0	0	0	(1)
Foreign currency translation adjustments	(45,541)	22,593	(31,604)	35,795
Total other comprehensive income	(45,541)	22,593	(31,604)	35,981
Comprehensive income	$ 26,022	$ 74,006	$ 79,154	$ 129,965

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.

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Amount after tax and 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, attributable to parent entity.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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