Income Taxes (Details 5) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Reduction in income tax expense, net of the related federal tax effects, that would result in a realization of unrecognized tax benefits	$ 1,400,000
Accrued liabilities for interest and penalties related to uncertain tax positions	469,000	1,100,000	730,000
Interest and penalties on uncertain tax positions, income tax expense	247,000	224,000	316,000
Reduction in income tax expense, net of the related deferred tax effects, that would result in a realization of unrecognized tax benefits for the reversal of accrued interest and penalties	341,000
Base year bad debt reserves	165,800,000	165,800,000
Unrecognized deferred federal income tax liability	$ 58,000,000	$ 58,000,000