Operating Segments and Geographic Information - Reconciliations of Other Segment Measures to Consolidated Totals (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment assets	$ 3,779,321	$ 3,840,613	$ 3,806,803
Cash and cash equivalents	420,610	561,108	848,116	$ 216,751
Goodwill	1,557,653	1,478,257	1,385,995
Intangible assets, less accumulated amortization	511,093	545,207	560,082
Deferred income taxes	56,018	42,549	33,706
Acquisition of property, plant and equipment	97,847	64,261	53,974
Reportable Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment assets	1,220,110	1,146,395	913,998
Acquisition of property, plant and equipment	94,834	62,759	53,582
Corporate assets
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total segment assets	13,837	67,097	64,906
Acquisition of property, plant and equipment	$ 3,013	$ 1,502	$ 392