Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Comprehensive Income
Net income (loss)	$ 2,298us-gaap_NetIncomeLoss	$ 4,331us-gaap_NetIncomeLoss
Derivative instruments
Reclassification adjustment for losses (gains) included in net income		(125)
Net gain (loss) recognized in other comprehensive income		(125)
Tax benefit (expense) related to items of other comprehensive income		46
Other comprehensive income (loss)		(79)
Total comprehensive income	$ 2,298us-gaap_ComprehensiveIncomeNetOfTax	$ 4,252us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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