Income Tax Expense (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2016 USD ($) Partnership	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) Partnership
Income Tax Expense [Abstract]
Investments in number of partnerships | Partnership	4		4
Investment amount in partnerships	$ 894,000		$ 959,000
Investment Tax Credit Carryforward [Member]
Tax Credit Carryforward [Line Items]
Investment tax credits	$ 995,000
Tax credits recognition period	6 years 8 months 12 days
Tax credits recognized as reduction of tax expense amount	$ 50,000	$ 50,000