Equity (Details) - Changes in AOCI by Component (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ (132,400)
Other comprehensive income (loss), net of tax	$ 219	$ (13,657)	(3,382)	$ (28,104)
Ending balance	(10,498)		(10,498)
Interest Rate Swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(12,158)	(2,410)	(3,079)	(1,740)
Change in AOCL/I before reclassifications to income	2,076	(7,457)	(9,376)	(9,910)
Reclassifications from AOCI to income during the period	1,138	1,647	3,511	3,430
Other comprehensive income (loss), net of tax	3,214	(5,810)	(5,865)	(6,480)
Ending balance	(8,944)	(8,220)	(8,944)	(8,220)
Defined Benefit Pension Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(4,757)	(5,922)	(4,832)	(6,028)
Change in AOCL/I before reclassifications to income	0	0	0	0
Reclassifications from AOCI to income during the period	37	53	112	159
Other comprehensive income (loss), net of tax	37	53	112	159
Ending balance	(4,720)	(5,869)	(4,720)	(5,869)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(31,088)	(27,285)	(36,491)	(13,402)
Change in AOCL/I before reclassifications to income	(3,032)	(7,900)	2,371	(21,783)
Reclassifications from AOCI to income during the period	0	0	0	0
Other comprehensive income (loss), net of tax	(3,032)	(7,900)	2,371	(21,783)
Ending balance	(34,120)	(35,185)	(34,120)	(35,185)
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(48,003)	(35,617)	(44,402)	(21,170)
Change in AOCL/I before reclassifications to income	(956)	(15,357)	(7,005)	(31,693)
Reclassifications from AOCI to income during the period	1,175	1,700	3,623	3,589
Other comprehensive income (loss), net of tax	219	(13,657)	(3,382)	(28,104)
Ending balance	$ (47,784)	$ (49,274)	$ (47,784)	$ (49,274)