Consolidated Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Income	$ 8,788us-gaap_NetIncomeLoss	$ 55,217us-gaap_NetIncomeLoss	$ 86,539us-gaap_NetIncomeLoss
Other comprehensive income (loss), before tax:
Unrealized gain (loss) on derivative instruments	(22)	89	(30)
Unrealized gain (loss) on available-for-sale securities	(14)	(40)	16
Other comprehensive income (loss), before tax	(36)	49	(14)
Tax benefit (expense) related to items of other comprehensive income	5us-gaap_OtherComprehensiveIncomeLossTax	16us-gaap_OtherComprehensiveIncomeLossTax	(5)us-gaap_OtherComprehensiveIncomeLossTax
Other comprehensive income (loss), net of tax	(31)	65	(19)
Comprehensive income	$ 8,757us-gaap_ComprehensiveIncomeNetOfTax	$ 55,282us-gaap_ComprehensiveIncomeNetOfTax	$ 86,520us-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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