Income Taxes - Effective Income Tax Expense (Benefit) Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory amount (computed at 35%)	$ 3,519	$ (212)	$ (5,776)
State income tax, net of federal benefit	(312)	(20)	564
Permanent differences	122	(13)	(743)
Permanent differences, incentive stock options	157	237	1,189
True up of deferred balances for non-qualified stock options	0	(571)	0
True up to prior year taxes	0	(401)	0
True up to prior year taxes	(311)	0	0
Other (net)	0	43	126
Total	$ 3,175us-gaap_IncomeTaxExpenseBenefit	$ (937)us-gaap_IncomeTaxExpenseBenefit	$ (4,640)us-gaap_IncomeTaxExpenseBenefit
Consolidated effective tax rate	31.58261%	154.62046%	27.90%
Federal statutory tax rate	35.00%	35.00%	35.00%

Effective Income Tax Rate Reconciliation, State Taxes Adjustments, Amount

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Income Tax Reconciliation, Permanent Differences

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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