Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income		$ 51,155	$ 53,040	$ 79,506	$ 90,776
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments		6,224	876	(13,883)	598
Interest rate hedges – net change in deferred (loss) gain		434	511	(670)	981
Pension – net change in deferred actuarial gain		53	14	106	29
Other comprehensive income (loss), net of tax	[1]	6,711	1,401	(14,447)	1,608
Comprehensive income		$ 57,866	$ 54,441	$ 65,059	$ 92,384

[1] Amounts in parentheses represent debits (deferred losses).