SCHEDULE IV - LOANS AND OTHER LENDING INVESTMENTS, Loans and Investments Carrying Amounts (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of the Company's loans and investments carrying amounts
Balance at beginning of year	$ 1,459,475,650	$ 1,523,699,653	$ 1,325,667,053
Additions during period:
New loan originations	944,250,824	900,666,405	591,537,200
Loan charge-offs	32,000,000	6,501,079	24,713,459
Funding of unfunded loan commitments	6,929,472	907,052	322,926
Accretion of unearned revenue	5,555,539	4,976,577	5,385,999
Charge-off on loan converted to real estate owned	2,500,000
Recoveries of reserves	2,042,263	9,315,724	2,215,443
Charge-off on loan converted to other assets			19,000,000
Deductions during period:
Loan payoffs	(865,595,986)	(941,279,252)	(324,358,463)
Loan paydowns	(84,707,265)	(26,558,929)	(54,261,753)
Use of loan charge-offs	(32,000,000)	(6,501,079)	(24,713,459)
Loan converted to real estate owned	(8,400,000)
Provision for loan losses	(6,509,149)	(9,026,712)	(6,500,000)
Unearned revenue and costs	(3,907,007)	(3,224,868)	(5,884,655)
Satisfaction of participation loan	(1,300,000)
Loan converted to other assets			(25,000,000)
Proceeds and receivables from sale of loans			(4,424,097)
Balance at end of year	$ 1,450,334,341	$ 1,459,475,650	$ 1,523,699,653