Mortgage-Backed Securities Narrative Tagging (Details) (USD $)	9 Months Ended						3 Months Ended										3 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Effective rate - minimum [Member]	Dec. 31, 2012 Effective rate - minimum [Member]	Sep. 30, 2013 Effective rate - maximum [Member]	Dec. 31, 2012 Effective rate - maximum [Member]	Dec. 31, 2012 Trust Portfolio--MBS Bonds [Member] Integer	Sep. 30, 2013 Trust Portfolio--MBS Bonds [Member]	Mar. 31, 2013 Trust Portfolio--MBS Bonds [Member]	Sep. 30, 2013 Trust Portfolio--MBS Bonds [Member] Effective rate - minimum [Member]	Sep. 30, 2013 Trust Portfolio--MBS Bonds [Member] Effective rate - maximum [Member]	Sep. 30, 2013 10% adverse [Member] Effective rate - minimum [Member]	Sep. 30, 2013 10% adverse [Member] Effective rate - maximum [Member]	Sep. 30, 2013 10% adverse [Member] Trust Portfolio--MBS Bonds [Member]	Sep. 30, 2013 10% adverse [Member] Trust Portfolio--MBS Bonds [Member] Effective rate - minimum [Member]	Sep. 30, 2013 10% adverse [Member] Trust Portfolio--MBS Bonds [Member] Effective rate - maximum [Member]	Sep. 30, 2012 LIFERS [Member]	Mar. 31, 2013 LIFERS [Member] Trust Portfolio--MBS Bonds [Member]	Dec. 31, 2012 LIFERS [Member] Trust Portfolio--MBS Bonds [Member]	Sep. 30, 2013 Georgia MBS Bonds [Member] Trust Portfolio--MBS Bonds [Member] Integer	Sep. 30, 2013 Georgia MBS Bonds [Member] LIFERS [Member] Trust Portfolio--MBS Bonds [Member]
Available-for-Sale Securities, Ownership Percentage	100.00%						100.00%										100.00%
Tolerable Range of Difference in Valuation	0.00%
Effective rate			6.30%	5.70%	9.80%	8.40%				3.60%	5.40%	6.90%	10.80%		4.40%	5.60%
Adverse change rate	10.00%							10.00%
Unrealized Loss	$ (2,971,715)	$ (4,289,886)					$ (413,665)	$ (5,411,720)						$ (2,000,000)
Number of Available for Sale Securities, Mortgage Backed Securities							5													3
Available for Sale Securities, not Including Premiums							31,600,000	43,310,000												10,000,000
TOB Financing								$ 24,500,000	$ 2,500,000									$ 500,000	$ 6,500,000		$ 2,200,000