Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating Activities
Net income	$ 40,012	$ 36,368
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	10,920	11,449
Deferred income taxes	(589)
Stock-based compensation	4,021	3,672
Loss on disposal of property, plant and equipment	168	169
Excess tax benefits from stock compensation	(2,437)	(12,677)
Other non-cash adjustments	(269)	(245)
Changes in operating assets and liabilities:
Accounts receivable	(44,005)	(7,698)
Inventories	6,792	7,789
Prepaid expenses and other assets	(310)	(415)
Accounts payable	(9,904)	(2,027)
Accrued expenses and other liabilities	3,626	(3,690)
Income taxes receivable/payable	4,126	12,630
Net cash provided by operating activities	12,151	45,325
Investing Activities
Expenditures for property, plant and equipment	(18,279)	(8,794)
Proceeds from sales of property, plant and equipment	35	48
Purchase of acquired company, net of cash acquired	(32)	(44)
Notes receivable, net		59
Net cash used in investing activities	(18,276)	(8,731)
Financing Activities
Borrowings under line of credit	199,000	139,000
Principal payments under line of credit	(150,500)	(136,000)
Repurchases of common stock	(52,081)	(52,892)
Proceeds from employee stock purchase and option plans	257	690
Excess tax benefits from stock compensation	2,437	12,677
Net cash used in financing activities	(887)	(36,525)
Net (decrease) increase in cash and cash equivalents	(7,012)	69
Cash and cash equivalents, beginning of period	9,544	3,772
Cash and cash equivalents, end of period	2,532	3,841
Supplemental Disclosure:
Cash paid for interest, net of capitalized interest	390	498
Cash paid for income taxes, net	$ 20,164	$ 9,342