Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill	$ 868,483		$ 868,483		$ 870,301	$ 851,372
Goodwill, Acquired During Period			24,778		43,655
Goodwill, Written off Related to Sale of Business Unit	(764)		764
Goodwill, Impairment Loss	(29,631)	$ 0	(29,631)	$ 0
Goodwill, Purchase Accounting Adjustments					(2,428)
Goodwill, Foreign Currency Translation Gain (Loss)			3,799		(22,298)
Reportable Segment [Domain]
Goodwill [Line Items]
Goodwill	680,168		680,168		655,039	660,792
Goodwill, Acquired During Period			24,778		6,254
Goodwill, Written off Related to Sale of Business Unit			0
Goodwill, Impairment Loss	0		0
Goodwill, Purchase Accounting Adjustments					(1,744)
Goodwill, Foreign Currency Translation Gain (Loss)			351		(10,263)
All Other Segment [Domain]
Goodwill [Line Items]
Goodwill	188,315		188,315		215,262	$ 190,580
Goodwill, Acquired During Period			0		37,401
Goodwill, Written off Related to Sale of Business Unit			(764)
Goodwill, Impairment Loss	$ (29,631)		(29,631)
Goodwill, Purchase Accounting Adjustments					(684)
Goodwill, Foreign Currency Translation Gain (Loss)			$ 3,448		$ (12,035)