CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating activities:
Net income	$ 225,475	$ 198,666
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	76,135	75,057
Equity-based compensation	12,841	11,303
Deferred income taxes	9,545	7,716
Other adjustments	30	(104)
Changes in certain assets and liabilities:
Accounts receivable	(118,818)	(153,364)
Inventories	(80,711)	(86,819)
Other assets	(105)	2,094
Accounts payable	66,332	133,809
Income taxes receivable/payable	63,962	96,319
Accrued expenses	(76,751)	(44,247)
Net cash provided by operating activities	177,935	240,430
Investing activities:
Purchases of property, plant and equipment	(50,606)	(41,677)
Purchase of short term investments	(40,000)
Other investing activities	229	26,918
Net cash used in investing activities	(90,377)	(14,759)
Financing activities:
Issuance of current and long-term debt	93,058
Repayment of current and long-term debt	(113,034)	(1,429)
Dividends paid	(36,797)	(34,130)
Purchases of treasury stock	(69,269)	(61,256)
Other financing activities	(5,180)	(3,532)
Net cash provided by (used in) financing activities	(131,222)	(100,347)
Increase (decrease) in cash and equivalents	(43,664)	125,324
Cash and equivalents at beginning of period	1,035,085	848,105
Cash and equivalents at end of period	991,421	973,429
Supplemental disclosure information:
Cash paid for interest	8,629	12,649
Cash paid for income taxes, net	$ (1,045)	$ 1,554