CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net income	$ 98,958	$ 75,899
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	10,183	8,903
Amortization of intangible assets	10,871	11,789
Amortization of debt issuance expenses	332	329
Share-based compensation expense	7,652	6,159
Deferred income taxes	(2,041)	1,293
Non-cash interest expense associated with forward starting swaps	1,632	1,677
Changes in (net of the effect from acquisitions):
Receivables	(30,816)	(20,058)
Inventories	(21,116)	(2,761)
Other current assets	16,881	6,570
Trade accounts payable	8,215	5,188
Accrued expenses	(27,273)	(11,565)
Other — net	(1,749)	1,556
Net cash flows provided by operating activities	71,729	84,979
Cash flows from investing activities
Purchases of property, plant and equipment	(10,009)	(10,162)
Other — net	(184)	546
Net cash flows (used in) investing activities	(10,193)	(9,616)
Cash flows from financing activities
Borrowings under revolving credit facilities	0	13,000
Payments under revolving credit facilities	0	(80,224)
Dividends paid	(28,945)	(26,327)
Proceeds from stock option exercises	6,590	6,074
Purchases of common stock	0	(7,005)
Shares surrendered for tax withholding	(10,750)	(5,647)
Settlement of foreign exchange contracts	6,618	738
Net cash flows (used in) financing activities	(26,487)	(99,391)
Effect of exchange rate changes on cash and cash equivalents	1,974	4,159
Net increase (decrease) in cash	37,023	(19,869)
Cash and cash equivalents at beginning of year	375,950	235,964
Cash and cash equivalents at end of period	412,973	216,095
Cash paid for:
Interest	355	760
Income taxes — net	10,942	5,888
Significant non-cash activities:
Capital expenditures for construction of new leased facility	$ 5,801	$ 0