Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	$ 3,148,366	$ 3,062,923
Ending Balance	3,396,772	3,148,366
Total accumulated other comprehensive loss included in shareholders' equity	3,329,861	3,087,358
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	(38,701)	(56,767)
Other comprehensive income (loss), before reclassifications	(14,161)	18,066
Ending Balance	(52,862)	(38,701)
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	150	(455)
Other comprehensive income (loss), before reclassifications	(3,472)	152
Reclassification adjustment	(228)	453
Ending Balance	(3,550)	150
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	(38,551)
Ending Balance	(56,412)	(38,551)
AOCI Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	754
Ending Balance	1,169	754
AOCI Attributable to Parent
AOCI Including Portion Attributable to Noncontrolling Interest [Abstract]
Beginning Balance	(37,797)	(56,031)
Ending Balance	(55,243)	(37,797)
Total accumulated other comprehensive loss included in shareholders' equity	$ (55,243)	$ (37,797)

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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