Fair Value (Schedule of Financial Instruments Utilizing Level 3 Inputs) (Details) (USD $)	6 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Mortgage Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 331,785,542
Total net transfers into/out of Level 3
Acquisitions	84,795,975	334,162,044
Proceeds from sales
Net accretion of discounts	3,423,653	3,059,231
Proceeds from principal repayments	(9,509,379)	(13,871,059)
Total losses (realized / unrealized) included in earnings	(4,302,177)	(6,344,877)
Total gains (realized / unrealized) included in earnings	27,360,106	14,780,203
Ending balance	433,553,720	331,785,542
The amount of total gains or (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets or liabilities still held at the reporting date	22,695,371	7,136,482
Residential Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	226,155,221	100,911,651
Total net transfers into/out of Level 3
Acquisitions	11,830,958	234,397,506
Proceeds from sales	(2,072,198)	(68,190,593)
Net accretion of discounts	2,603,804	3,727,702
Proceeds from principal repayments	(15,582,121)	(39,338,730)
Total losses (realized / unrealized) included in earnings	(468,061)	(9,138,009)
Total gains (realized / unrealized) included in earnings	4,825,933	3,785,694
Ending balance	227,293,536	226,155,221
The amount of total gains or (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets or liabilities still held at the reporting date	4,316,518	(2,822,969)
Other Investment Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance
Total net transfers into/out of Level 3
Acquisitions	10,676,953
Proceeds from sales
Net accretion of discounts	80,424
Proceeds from principal repayments
Total losses (realized / unrealized) included in earnings
Total gains (realized / unrealized) included in earnings	1,276,626
Ending balance	12,034,003
The amount of total gains or (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets or liabilities still held at the reporting date	$ 1,276,626