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Carrying value as of the balance sheet date, of securities sold under agreements to repurchase and the carrying value, as of the balance sheet date, of the outstanding borrowings under warehouse and revolving lines of credit.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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No definition available.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of debt outstanding.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

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No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Debt Obligations, Credit Facilities and Repurchase Agreements (Details) - USD ($)	1 Months Ended					3 Months Ended	9 Months Ended
	Sep. 30, 2017	Aug. 31, 2017	Jul. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2017	Sep. 30, 2017	Jan. 31, 2018	Oct. 31, 2017	Apr. 30, 2017	Feb. 28, 2017	Dec. 31, 2016
Debt Obligations
Debt Carrying Value	$ 562,326,537					$ 562,326,537	$ 562,326,537					$ 906,636,790
Collateral Carrying Value	$ 713,043,810					$ 713,043,810	$ 713,043,810					$ 1,041,761,233
Weighted Average Note Rate (as a percent)	2.99%					2.99%	2.99%					2.25%
Letter of credit
Debt Obligations
Maximum borrowing capacity	$ 50,000,000					$ 50,000,000	$ 50,000,000
Structured Business
Debt Obligations
Debt Carrying Value	234,339,350					234,339,350	234,339,350					$ 246,492,668
Collateral Carrying Value	$ 384,766,864					$ 384,766,864	$ 384,766,864					$ 381,446,074
Weighted Average Note Rate (as a percent)	3.58%					3.58%	3.58%					3.02%
Weighted average note rate including certain fees and costs (as a percent)	4.06%					4.06%	4.06%					3.42%
Unamortized deferred finance costs	$ 1,600,000					$ 1,600,000	$ 1,600,000					$ 1,900,000
Leverage on loans and investment portfolio, excluding the $3.0 million master security agreement used to finance leasehold improvements to corporate office (as a percent)	58.00%					58.00%	58.00%					64.00%
Structured Business \| $150 million repurchase facility
Debt Obligations
Debt Carrying Value	$ 149,157,816					$ 149,157,816	$ 149,157,816					$ 106,051,080
Collateral Carrying Value	$ 253,150,000					$ 253,150,000	$ 253,150,000					$ 183,827,574
Weighted Average Note Rate (as a percent)	3.63%					3.63%	3.63%					3.12%
Maximum borrowing capacity	$ 150,000,000					$ 150,000,000	$ 150,000,000		$ 225,000,000			$ 150,000,000
Additional borrowing capacity									$ 75,000,000
Structured Business \| $150 million repurchase facility \| Minimum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							2.25%
Structured Business \| $150 million repurchase facility \| Maximum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							3.50%
Structured Business \| $100 million repurchase facility
Debt Obligations
Debt Carrying Value	2,407,564					2,407,564	$ 2,407,564					21,598,322
Collateral Carrying Value	$ 6,600,000					$ 6,600,000	$ 6,600,000					$ 34,850,000
Weighted Average Note Rate (as a percent)	3.28%					3.28%	3.28%					2.96%
Maximum borrowing capacity	$ 100,000,000			$ 100,000,000		$ 100,000,000	$ 100,000,000					$ 100,000,000
Decrease in interest rate (as a percent)				(0.15%)
Advance rate (as a percent)				75.00%
Structured Business \| $100 million repurchase facility \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)				2.00%			2.00%
Structured Business \| $75 million credit facility - One
Debt Obligations
Debt Carrying Value	12,096,267					12,096,267	$ 12,096,267					38,703,886
Collateral Carrying Value	$ 28,088,500					$ 28,088,500	$ 28,088,500					$ 63,158,500
Weighted Average Note Rate (as a percent)	3.40%					3.40%	3.40%					2.94%
Maximum borrowing capacity	$ 75,000,000					$ 75,000,000	$ 75,000,000					$ 75,000,000
Structured Business \| $75 million credit facility - One \| Minimum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							2.125%
Structured Business \| $75 million credit facility - One \| Maximum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							2.50%
Structured Business \| $75 million credit facility - two
Debt Obligations
Debt Carrying Value	16,206,619					16,206,619	$ 16,206,619					23,276,773
Collateral Carrying Value	$ 42,300,000					$ 42,300,000	$ 42,300,000					$ 31,725,000
Weighted Average Note Rate (as a percent)	3.28%					3.28%	3.28%					2.81%
Maximum borrowing capacity	$ 75,000,000					$ 75,000,000	$ 75,000,000					$ 75,000,000
Structured Business \| $75 million credit facility - two \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							2.00%
Structured Business \| $50 million credit facility - one
Debt Obligations
Debt Carrying Value	25,000,000					25,000,000	$ 25,000,000					46,373,641
Collateral Carrying Value	$ 31,250,000					$ 31,250,000	$ 31,250,000					$ 58,000,000
Weighted Average Note Rate (as a percent)	3.28%					3.28%	3.28%					2.81%
Maximum borrowing capacity	$ 50,000,000					$ 50,000,000	$ 50,000,000					$ 50,000,000
Structured Business \| $50 million credit facility - one \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							2.00%
Structured Business \| $50 million credit facility - two
Debt Obligations
Debt Carrying Value	3,563,565					3,563,565	$ 3,563,565					7,956,000
Collateral Carrying Value	$ 4,625,000					$ 4,625,000	$ 4,625,000					$ 9,885,000
Weighted Average Note Rate (as a percent)	4.54%					4.54%	4.54%					4.08%
Maximum borrowing capacity	$ 50,000,000					$ 50,000,000	$ 50,000,000					$ 50,000,000
Structured Business \| $50 million credit facility - two \| Minimum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							2.50%
Structured Business \| $50 million credit facility - two \| Maximum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							3.25%
Structured Business \| $25.5 million credit facility
Debt Obligations
Debt Carrying Value	13,909,625					13,909,625	$ 13,909,625
Collateral Carrying Value	$ 18,753,364					$ 18,753,364	$ 18,753,364
Weighted Average Note Rate (as a percent)	3.78%					3.78%	3.78%
Maximum borrowing capacity	$ 25,500,000					$ 25,500,000	$ 25,500,000
Structured Business \| $25.5 million credit facility \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)	2.50%						2.50%
Structured Business \| $10 million credit facility
Debt Obligations
Debt Carrying Value	$ 10,000,000					$ 10,000,000	$ 10,000,000
Weighted Average Note Rate (as a percent)	3.78%					3.78%	3.78%
Maximum borrowing capacity	$ 10,000,000				$ 10,000,000	$ 10,000,000	$ 10,000,000					10,000,000
Structured Business \| $10 million credit facility \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)					2.50%		2.50%
Structured Business \| $3 million master security agreement
Debt Obligations
Debt Carrying Value	$ 1,997,894					$ 1,997,894	$ 1,997,894					$ 2,532,966
Weighted Average Note Rate (as a percent)	3.21%					3.21%	3.21%					3.21%
Maximum borrowing capacity	$ 3,000,000					$ 3,000,000	$ 3,000,000					$ 3,000,000
Structured Business \| $3 million master security agreement \| Minimum
Debt Obligations
Variable rate, spread (as a percent)							2.96%
Structured Business \| $3 million master security agreement \| Maximum
Debt Obligations
Variable rate, spread (as a percent)							3.42%
Agency Business
Debt Obligations
Debt Carrying Value	327,987,187					327,987,187	$ 327,987,187					660,144,122
Collateral Carrying Value	$ 328,276,946					$ 328,276,946	$ 328,276,946					$ 660,315,159
Weighted Average Note Rate (as a percent)	2.56%					2.56%	2.56%					1.96%
Unamortized deferred finance costs	$ 300,000					$ 300,000	$ 300,000					$ 300,000
Commitment amount expires in January 2018				$ 250,000,000
Agency Business \| $100 million repurchase facility
Debt Obligations
Debt Carrying Value	1,479,155					1,479,155	1,479,155
Collateral Carrying Value	$ 1,542,000					$ 1,542,000	$ 1,542,000
Weighted Average Note Rate (as a percent)	2.58%					2.58%	2.58%
Maximum borrowing capacity		$ 100,000,000
Agency Business \| $100 million repurchase facility \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)		1.35%					1.35%
Agency Business \| $100 million credit facility - two
Debt Obligations
Debt Carrying Value	$ 64,881,000					$ 64,881,000	$ 64,881,000					39,047,500
Collateral Carrying Value	$ 64,881,000					$ 64,881,000	$ 64,881,000					$ 39,047,500
Weighted Average Note Rate (as a percent)	2.53%					2.53%	2.53%					1.95%
Maximum borrowing capacity	$ 100,000,000			$ 100,000,000		$ 100,000,000	$ 100,000,000	$ 250,000,000				$ 100,000,000
Commitment amount expires in January 2018			$ 250,000,000
Decrease in interest rate (as a percent)				0.05%
Agency Business \| $100 million credit facility - two \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)				1.30%			1.30%
Agency Business \| $150 million credit facility - one
Debt Obligations
Debt Carrying Value	80,709,289					80,709,289	$ 80,709,289					268,530,211
Collateral Carrying Value	$ 80,786,203					$ 80,786,203	$ 80,786,203					$ 268,571,797
Weighted Average Note Rate (as a percent)	2.63%					2.63%	2.63%					2.05%
Maximum borrowing capacity	$ 150,000,000	$ 225,000,000	$ 150,000,000			$ 150,000,000	$ 150,000,000			$ 200,000,000		$ 150,000,000
Agency Business \| $150 million credit facility - one \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							1.40%
Agency Business \| $150 million credit facility - two
Debt Obligations
Debt Carrying Value	131,409,000					131,409,000	$ 131,409,000					210,009,449
Collateral Carrying Value	$ 131,559,000					$ 131,559,000	$ 131,559,000					$ 210,138,900
Weighted Average Note Rate (as a percent)	2.64%					2.64%	2.64%					2.05%
Maximum borrowing capacity	$ 150,000,000					$ 150,000,000	$ 150,000,000				$ 350,000,000	$ 150,000,000
Decrease in interest rate (as a percent)			0.05%
Agency Business \| $150 million credit facility - two \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)			1.35%				1.35%
Agency Business \| $500 million multifamily ASAP agreement
Debt Obligations
Debt Carrying Value	49,508,743					49,508,743	$ 49,508,743					142,556,962
Collateral Carrying Value	$ 49,508,743					$ 49,508,743	$ 49,508,743					$ 142,556,962
Weighted Average Note Rate (as a percent)	2.28%					2.28%	2.28%					1.65%
Maximum borrowing capacity	$ 500,000,000					$ 500,000,000	$ 500,000,000					$ 400,000,000
Agency Business \| $500 million multifamily ASAP agreement \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							1.05%
Agency Business \| $500 million multifamily ASAP agreement \| Minimum \| LIBOR
Debt Obligations
Variable rate, spread (as a percent)							0.35%
Agency Business \| $50 million credit facility - September 2020
Debt Obligations
Maximum borrowing capacity	50,000,000					$ 50,000,000	$ 50,000,000
Decrease in interest rate (as a percent)						0.125%
Credit facility, sublimit to finance healthcare related loans	$ 5,000,000					$ 5,000,000	$ 5,000,000
Fixed interest rate (as a percent)	2.875%					2.875%	2.875%
Fannie Mae \| Agency Business \| $50 million credit facility - September 2020
Debt Obligations
Outstanding letters of credit	$ 42,000,000					$ 42,000,000	$ 42,000,000
Freddie Mac \| Agency Business \| $50 million credit facility - September 2020
Debt Obligations
Outstanding letters of credit	$ 5,000,000					$ 5,000,000	$ 5,000,000