Comprehensive Income (Reclassification Out of Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Provision for Income Taxes	$ (33,126,019)	$ (20,323,345)
Amounts Reclassified from Other Comprehensive Income [Member] | Unrealized gains(losses) on available-for-sale securities [Member]
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Realized gain (loss) on sale of securities	5,023,421	2,822,207
Provision for Income Taxes	(1,758,197)	(987,772)
Total reclassifications for the period	$ 3,265,224	$ 1,834,435