Income Taxes (Details Textuals) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Deferred tax asset, general business tax credit carryforwards		$ 29,000,000
Deferred tax asset, alternative minimum tax credit carryforwards		267,000,000
Deferred tax assets, state net operating loss and credit carry-forwards		39,000,000	43,000,000
Valuation allowance		31,000,000	37,000,000
Unrecognized tax benefits that would impact effective tax rate		2,000,000	2,000,000
Significant change in unrecognized tax benefit is reasonable possible, amount of unrecorded benefit		6,000,000
Interest on income taxes accrued		1,000,000	1,000,000
Income tax penalties accrued		0
Interest on income taxes expense	$ (1,000,000)