CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income	$ 69,421	$ 111,422	$ 119,433
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	21,215	18,012	16,830
Amortization of intangibles	19,468	17,041	19,940
Net (gain) loss on sale of property, plant and equipment	(10,148)	(8,046)	101
Loss on debt extinguishment	280	799	1,895
Deferred income taxes	(2,976)	(14,682)	4,044
Stock-based compensation	10,169	10,429	12,038
Non-cash interest expense	1,745	2,258	3,475
Impairment of goodwill and other intangibles	24,968	0	1,663
Accounts receivable	(39,539)	31,943	(809)
Inventories	(18,713)	(13,158)	24,969
Prepaid expenses and other	4,548	(2,014)	(10,147)
Accounts payable and accrued liabilities	32,653	(963)	(13,002)
Other, net	(620)	(8,662)	(1,680)
Net cash provided by operating activities	112,471	144,379	178,750
Cash flows from investing activities
Capital expenditures	(34,009)	(26,056)	(20,342)
Proceeds from sale of property, plant and equipment	17,776	10,860	19
Acquisitions, net of cash acquired	0	(323,487)	0
Other, net	3,060	6,443	3,014
Net cash used in investing activities	(13,173)	(332,240)	(17,309)
Cash flows from financing activities
Proceeds from exercise of stock options	961	5,790	4,831
Borrowings under senior notes	0	325,000	0
Dividends paid	(17,768)	(15,315)	0
Borrowings under revolving credit facilities	937	713	618
Payments under revolving credit facilities	(937)	(713)	(618)
Principal payments under capital lease obligations	(290)	(600)	(779)
Proceeds from issuance of term loan credit facility	0	377,519	0
Principal payments under term loan credit facility	(1,880)	(386,577)	(1,928)
Principal payments under industrial revenue bond	(93)	(583)	(473)
Debt issuance costs paid	(476)	(6,783)	0
Convertible senior notes repurchase	(80,200)	(8,045)	(98,922)
Stock repurchase	(58,383)	(74,491)	(79,556)
Net cash provided by (used in) financing activities	(158,129)	215,915	(176,827)
Cash and cash equivalents:
Net increase (decrease) in cash and cash equivalents	(58,831)	28,054	(15,386)
Cash and cash equivalents at beginning of year	191,521	163,467	178,853
Cash and cash equivalents at end of year	132,690	191,521	163,467
Supplemental disclosures of cash flow information:
Cash paid for interest	27,386	9,479	12,656
Cash paid for income taxes	$ 24,243	$ 41,391	$ 68,870