Company-Obligated Mandatorily Redeemable Capital Securities (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Sep. 21, 2006
Floating Rate Junior Subordinated Deferrable Interest Debentures [Member]
Debt Instrument [Line Items]
Principal amount of debt	$ 4,000,000
Maturity date	Dec. 31, 2036
Floating Rate Capital Securities [Member]
Class of Stock [Line Items]
Face amount of capital securities		4,000,000
Capital securities, basis spread on variable rate (in hundredths)	1.70%
Capital securities, description of variable rate basis	three month LIBOR
Capital securities	$ 4,124,000
Callable period of capital securities	5 years