Long-Term Debt Obligations (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Future principal payments of long-term debt
2015	$ 317
2016	755
2017	673
2018	76
2019	38,525
Long-term Debt	40,346us-gaap_LongTermDebt	2,000us-gaap_LongTermDebt
Debt and Capital Lease Obligations, Total	40,346us-gaap_DebtAndCapitalLeaseObligations
Interest expense
Interest expense on notes to former owners	38us-gaap_InterestExpenseRelatedParty	97us-gaap_InterestExpenseRelatedParty	255us-gaap_InterestExpenseRelatedParty
Interest expense on borrowings and unused commitment fees	790	278	444
Letter of credit fees	747fix_LetterOfCreditFeesAmount	731fix_LetterOfCreditFeesAmount	667fix_LetterOfCreditFeesAmount
Amortization of debt financing costs	283	245	229
Total	$ 1,858us-gaap_InterestExpense	$ 1,351us-gaap_InterestExpense	$ 1,595us-gaap_InterestExpense

Represents the amount of fees associated with the letter of credit.

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Amount of noncash expense included in interest expense to allocate debt discount and premium, and the costs to issue debt and obtain financing over the related debt instruments. Alternate captions include noncash interest expense.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of interest expense incurred on a debt or other obligation to related party.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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