Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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The outstanding amount of commercial loans.

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

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Amount of the contractual principal due as of the balance sheet date.

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Represents the weighted average duration of a group of mortgage loan receivables.

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Reflects the percentage of mortgage loans charging borrowers variable or adjustable rates of interest.

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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.

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The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

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Amount of loan with variable or adjustable rate of interest.

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Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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The cash inflow from earnings received from real estate partnerships.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Loans - Held for Investment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Investments in loans
Total gross loans	$ 10,384,421		$ 10,384,421		$ 9,833,405
Loan loss allowance (loans held-for-investment)	(33,306)	$ (31,127)	(33,306)	$ (31,127)	(39,151)	$ (4,330)
Carrying Value	10,351,115	8,095,162	10,351,115	8,095,162	9,794,254	$ 7,382,641
Proceeds from borrowings			3,271,785	3,001,735
Payment of debt			2,679,056	2,410,574
Face Amount	10,399,912		10,399,912		9,876,545
Loans with variable rates of interest	$ 8,300,000		$ 8,300,000
Loans with variable rates of interest (as a percent)	94.80%		94.80%
Weighted average spread of loans (as a percent)	4.20%		4.20%
Total loans held-for-investment
Investments in loans
Total gross loans	$ 8,797,100		$ 8,797,100		8,571,507
Face Amount	8,840,351		8,840,351		8,610,457
Loans held-for-sale
Investments in loans
Total gross loans	1,587,321		1,587,321
Loans held-for-sale, residential
Investments in loans
Total gross loans	1,156,778		1,156,778		623,660
Face Amount	1,124,838		$ 1,124,838		$ 609,571
Weighted Average Life			5 years		6 years 7 months 6 days
Loans held-for-sale, residential \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			6.20%		6.30%
Loans held-for-sale, commercial
Investments in loans
Total gross loans	215,620		$ 215,620		$ 94,117
Carrying amount of commercial loans					47,622
Face Amount	215,425		$ 215,425		$ 94,916
Weighted Average Life			9 years 8 months 12 days		6 years 2 months 12 days
Loans held-for-sale, commercial \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			4.20%		5.40%
Loans Held For Sale Infrastructure
Investments in loans
Total gross loans	214,923		$ 214,923		$ 469,775
Face Amount	219,298		$ 219,298		$ 486,909
Weighted Average Life			1 year 6 months		3 months 18 days
Loans Held For Sale Infrastructure \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			4.10%		3.50%
Loans transferred as secured borrowings
Investments in loans
Total gross loans					$ 74,346
Face Amount					$ 74,692
Weighted Average Life					1 year 3 months 18 days
Loans transferred as secured borrowings \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)					7.10%
First mortgage loan participation \| Total loans held-for-investment
Investments in loans
Total gross loans	6,879,248		$ 6,879,248		$ 6,607,117
Face Amount	6,905,735		$ 6,905,735		$ 6,631,236
Weighted Average Life			2 years		2 years
First mortgage loan participation \| Total loans held-for-investment \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			6.40%		6.90%
First priority infrastructure receivables \| Total loans held-for-investment
Investments in loans
Total gross loans	1,356,511		$ 1,356,511		$ 1,456,779
Face Amount	1,367,336		$ 1,367,336		$ 1,465,828
Weighted Average Life			4 years 7 months 6 days		4 years 6 months
First priority infrastructure receivables \| Total loans held-for-investment \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			5.90%		5.70%
Mortgage, Residual Profit Participation \| Retail and Hospitality Property
Investments in loans
Total distributions received from residual profit participation	0	$ 12,300	$ 0	$ 12,300
Subordinated mortgages \| Total loans held-for-investment
Investments in loans
Total gross loans	52,926		52,926		$ 52,778
Face Amount	54,092		$ 54,092		$ 53,996
Weighted Average Life			3 years 2 months 12 days		3 years 8 months 12 days
Subordinated mortgages \| Total loans held-for-investment \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			8.80%		8.90%
Mezzanine Loans
Investments in loans
Carrying Value	890,000,000		$ 890,000,000		$ 1,000
Mezzanine Loans \| Total loans held-for-investment
Investments in loans
Total gross loans	446,484		446,484		393,832
Face Amount	447,537		$ 447,537		$ 394,739
Weighted Average Life			2 years 1 month 6 days		2 years
Mezzanine Loans \| Total loans held-for-investment \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			11.10%		10.60%
Other \| Total loans held-for-investment
Investments in loans
Total gross loans	61,931		$ 61,931		$ 61,001
Face Amount	$ 65,651		$ 65,651		$ 64,658
Weighted Average Life			2 years		2 years 6 months
Other \| Total loans held-for-investment \| Weighted-average
Investments in loans
Weighted Average Coupon (as a percent)			8.20%		8.20%