CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Activities:
Net income	$ 48,283	$ 46,320	$ 53,412
Adjustments to reconcile net income to cash from operating activities:
Depreciation and amortization	37,847	34,054	26,268
Stock-based compensation expense	11,275	9,643	7,533
Deferred income taxes	7,382	3,668	8,435
Equity in income of unconsolidated joint ventures	(4,146)	(2,890)	(4,123)
Dividends received from unconsolidated joint ventures	2,757	3,463	3,849
Pension and postretirement benefits	(2,822)	(1,512)	1,976
Loss from the disposal of property, plant and equipment	225	295	(69)
Impairment of assets/investments	0	150
Bad debt expense	1,321	1,085	250
Loss on disposition of a business	0	4,819	0
Changes in operating assets and liabilities excluding effects of acquisition and disposition of businesses:
Accounts receivable	(13,005)	8,971	(10,438)
Inventories	9,689	(10,608)	(6,054)
Pension contribution	(842)	(7,737)	(14,645)
Other current assets	1,933	(1,278)	1,063
Accounts payable and other accrued expenses	21,472	(17,632)	16,638
Other, net	(4,402)	3,111	1,112
Net cash provided by operating activities	116,967	73,922	85,207
Investing Activities:
Capital expenditures	(18,136)	(24,837)	(28,755)
Proceeds from life insurance	275	2,682	0
Loss from the sale of property, plant and equipment, net	0	0	69
Other investing activities	0	(1,000)	166
Proceeds from the sale of a business	0	1,265	0
Acquisition of business, net of cash received	(133,943)	(158,407)	0
Net cash used in investing activities	(151,804)	(180,297)	(28,520)
Financing Activities:
Proceeds from long term borrowings	166,000	125,000	0
Repayment of debt principal and long term lease obligation	(103,760)	(6,641)	(17,797)
Debt issuance costs	0	(293)	0
Repurchases of capital stock	(7,995)	(39,993)	0
Proceeds from issuance of capital stock, net	4,143	6,967	20,513
Issuance of restricted stock	(1,377)	(2,740)	(1,542)
Proceeds from issuance of shares to employee stock purchase plan	858	727	693
Net cash provided by financing activities	57,869	83,027	1,867
Effect of exchange rate fluctuations on cash	149	(9,441)	(13,063)
Net increase (decrease) in cash and cash equivalents	23,181	(32,789)	45,491
Cash and cash equivalents at beginning of year	204,586	237,375	191,884
Cash and cash equivalents at end of year	$ 227,767	$ 204,586	$ 237,375