Loans and Investments, Impaired Loans (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Changes in allowance for loan losses
Allowance at beginning of period	$ 81,255,922	$ 83,831,575	$ 83,711,575	$ 86,761,575
Provision for loan losses	2,000,000		2,000,000	59,005
Charge-offs				(2,959,005)
Recoveries of reserves		(15,000)	(2,455,653)	(45,000)
Allowance at end of period	$ 83,255,922	$ 83,816,575	$ 83,255,922	$ 83,816,575
Ratio of net recoveries (in percentage)	0.10%		0.10%
Ratio of net charge-offs (in percentage)		(0.20%)		(0.20%)
Impaired bridge loans, paid off	$ 1,800,000			$ 1,800,000
Preferred equity investments
Changes in allowance for loan losses
Carrying value of loans	34,800,000		$ 34,800,000
Bridge loans
Changes in allowance for loan losses
Recoveries of reserves			(700,000)
Carrying value of loans	4,800,000	$ 4,800,000	4,800,000	$ 4,800,000
Mezzanine loans
Changes in allowance for loan losses
Recoveries of reserves	(1,800,000)		(1,800,000)
Paid off in full	$ 1,800,000		$ 1,800,000

Reflects the percentage derived from charge-offs to the average loans and investments outstanding.

No definition available.

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- Definition

Reflects the percentage derived from net recoveries to the average loans and investments outstanding.

+ References

No definition available.

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- Definition

Represents information pertaining to the amount received on the impaired financing receivable, paid off.

+ References

No definition available.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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- Definition

The carrying amount of the outstanding balance due under the mortgage loan.

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- Definition

The cash inflow from proceeds from sale of receivables arising from the mortgage note on real estate; includes collections on mortgage notes receivable that are not classified as operating cash flows.

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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