Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net Income	$ 19,867	$ 11,378	$ 17,623
Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities
Depreciation and amortization	29,024	30,926	29,413
Asset impairments	0	6,975	0
Stock-based compensation expense	3,725	2,438	1,959
Deferred income taxes	345	(1,551)	1,098
Excess tax benefits from stock-based compensation	(140)	0	0
(Recovery of) provision for doubtful accounts	(237)	(77)	78
Other	(5,713)	5,337	181
Changes in Assets and Liabilities:
Accounts receivable	1,086	5,468	(1,204)
Inventories	(2,335)	6,962	5,870
Production cost of contracts	(3,513)	(5,101)	(1,324)
Other assets	4,800	(12,173)	6,829
Accounts payable	410	4,533	(8,097)
Accrued and other liabilities	6,103	(9,153)	(4,892)
Net Cash Provided by Operating Activities	53,422	45,962	47,534
Cash Flows from Investing Activities
Purchases of property and equipment	(18,096)	(12,403)	(15,813)
Proceeds from sales of assets	91	139	31
Insurance recoveries related to property and equipment	2,550	0	0
Net Cash Used in Investing Activities	(15,455)	(12,264)	(15,782)
Cash Flows from Financing Activities
Repayment of term loan and other debt	(42,650)	(33,024)	(26,478)
Debt issue cost paid	0	(365)	0
Excess Tax Benefit from Share-based Compensation, Financing Activities	140	0	0
Net proceeds from issuance of common stock under stock plans	1,356	1,968	(186)
Net Cash Used in Financing Activities	(41,154)	(31,421)	(26,664)
Net (Decrease) Increase in Cash and Cash Equivalents	(3,187)	2,277	5,088
Cash and Cash Equivalents at Beginning of Year	48,814	46,537	41,449
Cash and Cash Equivalents at End of Year	45,627	48,814	46,537
Supplemental Disclosures of Cash Flow Information
Interest paid	25,105	27,614	31,505
Taxes paid	3,476	7,835	1,953
Non-cash activities:
Purchases of property and equipment not paid	$ 1,458	$ 1,000	$ 0