Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities:
Net earnings	$ 48,096	$ 40,048
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	33,170	34,383
Stock compensation expense	4,348	5,646
Deferred income taxes	(59)	656
Provision for doubtful accounts	42	160
Foreign currency transaction loss	304	43
Loss on disposal of assets	239	319
Changes in assets and liabilities
Accounts receivable	485	(522)
Inventories	682	5,502
Prepaid expenses and other current assets	(398)	1,996
Accounts payable and accrued expenses	(3,499)	2,404
Income taxes	(4,373)	(10,118)
Other	417	(700)
Net cash provided by operating activities	79,454	79,817
Cash flows from investing activities:
Cash paid for acquisitions, net of cash acquired	(17,393)	(110,601)
Capital expenditures	(17,676)	(18,801)
Proceeds from insurance	2,000	1,000
Intangible assets acquired	(408)	(765)
Net cash used in investing activities	(33,477)	(129,167)
Cash flows from financing activities:
Proceeds from revolving loan	22,000	65,000
Principal payments on revolving loan	(41,000)	(37,000)
Principal payments on long-term debt	(26,250)	(26,250)
Principal payment on acquired debt	(2,384)	(884)
Proceeds from stock options exercised	9,524	5,985
Excess tax benefits from stock compensation	0	1,935
Dividends paid	(12,069)	(10,727)
Purchase of treasury stock	(1,833)	(1,478)
Net cash used in financing activities	(52,012)	(3,419)
Effect of exchange rate changes on cash	2,133	507
Decrease in cash and cash equivalents	(3,902)	(52,262)
Cash and cash equivalents beginning of period	38,643	84,795
Cash and cash equivalents end of period	$ 34,741	$ 32,533