Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows provided by (used in) operating activities:
Net income	$ 269,659	$ 153,351	$ 172,413
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	174,062	143,058	142,192
Amortization of debt issuance costs	4,259	4,139	4,156
Rationalization charges	5,826	19,061	14,407
Stock compensation expense	14,639	13,018	12,077
Loss on early extinguishment of debt	7,052	0	0
Deferred income tax (benefit) provision	(114,969)	45,011	(13,278)
Other changes that provided (used) cash, net of effects from acquisitions:
Trade accounts receivable, net	(37,107)	(10,867)	12,287
Inventories	(17,228)	19,960	(97,576)
Trade accounts payable	84,102	52,752	43,822
Accrued liabilities	4,321	(20,145)	37,640
Other, net	(4,851)	(24,787)	7,625
Net cash provided by operating activities	389,765	394,551	335,765
Cash flows provided by (used in) investing activities:
Purchases of businesses, net of cash acquired	(1,023,848)	0	(690)
Capital expenditures	(174,429)	(191,893)	(237,302)
Proceeds from asset sales	600	11,555	903
Net cash used in investing activities	(1,197,677)	(180,338)	(237,089)
Cash flows provided by (used in) financing activities:
Borrowings under revolving loans	1,172,079	919,482	732,091
Repayments under revolving loans	(1,316,758)	(797,106)	(729,843)
Changes in outstanding checks – principally vendors	8,851	(22,819)	18,961
Proceeds from issuance of long-term debt	1,789,200	0	7,538
Repayments of long-term debt	(755,037)	(67,412)	(37,304)
Debt issuance costs	(16,964)	0	0
Dividends paid on common stock	(40,493)	(40,877)	(39,741)
Repurchase of common stock	(4,123)	(280,736)	(173,024)
Net cash provided by (used in) financing activities	836,755	(289,468)	(221,322)
Cash and cash equivalents:
Net increase (decrease)	28,843	(75,255)	(122,646)
Balance at beginning of year	24,690	99,945	222,591
Balance at end of year	53,533	24,690	99,945
Interest paid, net	97,595	65,471	63,954
Income taxes paid, net of refunds	$ 70,239	$ 58,147	$ 49,690

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