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 (loss)	$ 6,877us-gaap_NetIncomeLoss	$ 331us-gaap_NetIncomeLoss	$ (11,866)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation and amortization	23,451	21,538	21,570
Deferred financing cost amortization	0us-gaap_AmortizationOfFinancingCosts	52us-gaap_AmortizationOfFinancingCosts	103us-gaap_AmortizationOfFinancingCosts
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Stock-based compensation	1,594us-gaap_ShareBasedCompensation	2,141us-gaap_ShareBasedCompensation	3,115us-gaap_ShareBasedCompensation
(Gain)/Loss on sale of property and equipment	(359)	153	1,822
Change in contingent liability related to earnout	0	(271)	0
Change in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable	(4,202)	4,571	(26,966)
Income tax receivable	0	2,125	10,888
Inventory	(3,702)us-gaap_IncreaseDecreaseInInventories	(3,024)us-gaap_IncreaseDecreaseInInventories	(497)us-gaap_IncreaseDecreaseInInventories
Note receivable	0	46	5
Prepaid expenses and other	(695)	(200)	(497)
Costs and estimated earnings in excess of billings on uncompleted contracts	(19,725)	(5,611)	(4,133)
Accounts payable	(1,178)	(6,405)	18,826
Accrued liabilities	4,428	(808)	2,803
Income tax payable	538	207	252
Billings in excess of costs and estimated earnings on uncompleted contracts	2,109	(1,774)	10,704
Deferred revenue	(53)	(58)	(57)
Net cash provided by operating activities	11,945	13,033	24,438
Cash flows from investing activities:
Proceeds from sale of property and equipment	1,005	750	374
Purchase of property and equipment	(18,711)	(12,760)	(24,647)
Net cash used in investing activities	(42,787)	(12,010)	(33,273)
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Payments made on borrowings from Credit Facility	(1,557)us-gaap_RepaymentsOfDebt	(4,057)us-gaap_RepaymentsOfDebt	(5,379)us-gaap_RepaymentsOfDebt
Contributions from noncontrolling interest	0	(50)	34
Exercise of stock options	869	859	298
Excess tax benefit from stock option exercise	0	0	0
Increase in loan costs	0us-gaap_PaymentsOfFinancingCosts	0us-gaap_PaymentsOfFinancingCosts	(13)us-gaap_PaymentsOfFinancingCosts
Purchase of shares into treasury	(436)us-gaap_PaymentsForRepurchaseOfEquity	0us-gaap_PaymentsForRepurchaseOfEquity	0us-gaap_PaymentsForRepurchaseOfEquity
Net cash (used in) provided by financing activities	28,876	(3,248)	12,940
Net change in cash and cash equivalents	(1,966)	(2,225)	4,105
Cash and cash equivalents at beginning of period	40,859	43,084	38,979
Cash and cash equivalents at end of period	38,893	40,859	43,084
Supplemental disclosures of cash flow information, cash paid during the period for:
Interest	742us-gaap_InterestPaid	483us-gaap_InterestPaid	697us-gaap_InterestPaid
Taxes (net of refunds)	770us-gaap_IncomeTaxesPaidNet	(3,045)us-gaap_IncomeTaxesPaidNet	(14,039)us-gaap_IncomeTaxesPaidNet
Supplemental disclosure of non cash transaction:
Fair value of earnout from acquisition of business in Alaska	0us-gaap_OtherNoncashExpense	0us-gaap_OtherNoncashExpense	271us-gaap_OtherNoncashExpense
Acquisition of business in Alaska
Cash flows from investing activities:
Payments for acquisition of businesses	0	0	(9,000)
Acquisition of business in Pacific Northwest
Cash flows from investing activities:
Payments for acquisition of businesses	$ (25,081)	$ 0	$ 0

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Other expenses or losses included in net income that result in no cash outflows or inflows in the period and are not separately disclosed.

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The cash outflow to reacquire common and preferred stock.

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The cash outflow for loan and debt issuance costs.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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-Publisher FASB

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-Subparagraph (SX 210.4-08.(f))

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-Subparagraph (b)

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Amount of cash inflow (outflow) from (to) a noncontrolling interest. Excludes dividends paid to the noncontrolling interest.

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-Publisher FASB

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-Topic 230

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-Section 45

-Paragraph 15

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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-Publisher FASB

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-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

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-Topic 718

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-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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No definition available.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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