Equity (Details) - Changes in AOCI by Component (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 60,878
Other comprehensive income (loss), net of tax	1,851	$ (5,028)
Ending balance	102,817
Interest Rate Swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,409)	(3,079)
Change in AOCL/I before reclassifications to income	(3,393)	(8,357)
Reclassifications from AOCI to income during the period	825	1,224
Other comprehensive income (loss), net of tax	(2,568)	(7,133)
Ending balance	(3,977)	(10,212)
Defined Benefit Pension Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(5,797)	(4,832)
Change in AOCL/I before reclassifications to income	0	0
Reclassifications from AOCI to income during the period	48	37
Other comprehensive income (loss), net of tax	48	37
Ending balance	(5,749)	(4,795)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(42,477)	(36,491)
Change in AOCL/I before reclassifications to income	4,371	2,068
Reclassifications from AOCI to income during the period	0	0
Other comprehensive income (loss), net of tax	4,371	2,068
Ending balance	(38,106)	(34,423)
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(49,683)	(44,402)
Change in AOCL/I before reclassifications to income	978	(6,289)
Reclassifications from AOCI to income during the period	873	1,261
Other comprehensive income (loss), net of tax	1,851	(5,028)
Ending balance	$ (47,832)	$ (49,430)