Investment and Mortgage-Backed Securities, Available for Sale (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015 security	Mar. 31, 2014	Dec. 31, 2014 security
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	$ 425,229,107		$ 420,876,924
Available-for-sale Securities, Fair Value Disclosure	434,502,629		429,700,540
Available For Sale Securities Pledged as Collateral, Amortized Cost Basis	119,600,000		120,700,000
Available-for-sale Securities Pledged as Collateral, Fair Value	123,800,000		124,400,000
Proceeds From Sale of Available For Sale Securities Including Mortgage Backed Securities	36,400,000	13,900,000
Percent of unrealized losses for securities in a continuous loss position for 12 months or more	44.60%		67.80%
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	13		24
Available-for-sale Securities, Gross Realized Losses	47,000	224,000
GNMA Mortgage-Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	160,600,000		156,800,000
Available-for-sale Securities, Fair Value Disclosure	164,700,000		160,600,000
Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	$ 1,533,817	$ 309,000