Stockholders' Equity (Changes in Accumulated Other Comprehensive Loss by Component) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive (loss) income, beginning of period	$ 4,163	$ (14,140)	$ (2,497)	$ (5,290)
Translation adjustments	1,783	(887)	4,294	(6,615)
Accumulated other comprehensive income (loss), end of period	6,291	(14,476)	6,291	(14,476)
Gains and losses on cash flow hedges [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive (loss) income, beginning of period	1,048	(4,445)	(3,101)	(1,323)
Other comprehensive (loss) income before reclassifications, net of tax effects	(692)	(200)	2,438	(3,473)
Amounts reclassified from accumulated other comprehensive (loss) income to interest expense	1,408	1,018	2,784	1,223
Tax benefit included in provision for income taxes	(371)	(267)	(728)	(321)
Total amounts reclassified from accumulated other comprehensive (loss) income	1,037	751	2,056	902
Net current-period other comprehensive income (loss)	345	551	4,494	(2,571)
Accumulated other comprehensive income (loss), end of period	1,393	(3,894)	1,393	(3,894)
Other comprehensive income (loss), unrealized gain (loss) on derivatives arising during period, tax	244	71	(856)	1,225
Foreign currency translation adjustment [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive (loss) income, beginning of period	3,115	(9,695)	604	(3,967)
Translation adjustments	1,783	(887)	4,294	(6,615)
Accumulated other comprehensive income (loss), end of period	$ 4,898	$ (10,582)	$ 4,898	$ (10,582)

Accumulated Other Comprehensive Income [Roll Forward]

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The amount of gains (losses) reclassified in the period from accumulated other comprehensive income (loss) to earnings.

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Net of tax amount of other comprehensive income (loss) attributable to the parent entity before reclassifications into income.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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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.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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