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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Regulation S-X (SX)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
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Amount of financing receivable reclassified to held for investment.

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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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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Amount of financing receivable reclassified to held-for-sale.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
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Loans - Held for Investment (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Investments in loans
Carrying Value	$ 15,534,090	$ 12,217,352
Face Amount	15,552,428	12,262,840
Credit loss allowances	(57,573)	(77,444)
Total net loans	15,476,517	12,139,908	$ 11,931,325	$ 11,470,224
Loans held for investment
Investments in loans
Carrying Value	13,350,571	11,164,517
Face Amount	13,430,893	11,230,344
Credit loss allowances	(57,573)	(77,444)
Loans held-for-sale
Investments in loans
Carrying Value	2,183,519	1,052,835
Face Amount	2,121,535	1,032,496
Total net loans	2,183,519	1,052,835	1,012,673	884,150
Commercial Portfolio Segment
Investments in loans
Carrying Value	11,561,011
Commercial Portfolio Segment \| Loans held for investment
Investments in loans
Carrying Value	11,561,011	9,653,560
Face Amount	11,619,682	9,703,608
Credit loss allowances	(48,359)	(69,611)
Total net loans	11,512,652	9,583,949	9,118,177	8,517,054
Infrastructure Portfolio Segment
Investments in loans
Carrying Value	1,698,061
Reclassification to held for investment	30,700
Infrastructure Portfolio Segment \| Loans held for investment
Investments in loans
Carrying Value	1,698,061	1,420,273
Face Amount	$ 1,719,931	$ 1,439,940
Weighted Average Life	3 years 10 months 24 days	4 years 3 months 18 days
Credit loss allowances	$ (9,214)	$ (7,833)
Total net loans	$ 1,688,847	$ 1,412,440	1,544,068	1,397,448
Infrastructure Portfolio Segment \| Loans held for investment \| Weighted-average
Investments in loans
Weighted Average Coupon	4.30%	4.40%
Infrastructure Portfolio Segment \| Loans held-for-sale
Investments in loans
Carrying Value	$ 84,253	$ 120,540
Face Amount	$ 84,457	$ 120,900
Weighted Average Life	1 year 6 months	3 years 2 months 12 days
Infrastructure Portfolio Segment \| Loans held-for-sale \| Weighted-average
Investments in loans
Weighted Average Coupon	2.80%	3.10%
Residential Portfolio Segment
Investments in loans
Weighted Average Life	29 years 6 months	27 years 10 months 24 days
Reclassification to held for investment	$ 94,200
Reclassification to held-for-sale	94,900
Residential Portfolio Segment \| Loans held for investment
Investments in loans
Total net loans	91,499	$ 90,684	$ 256,407	$ 671,572
RMBS, fair value option \| Loans held-for-sale
Investments in loans
Carrying Value	1,813,458	841,963
Face Amount	$ 1,758,342	$ 820,807
RMBS, fair value option \| Loans held-for-sale \| Weighted-average
Investments in loans
Weighted Average Coupon	4.30%	6.00%
CMBS, fair value option \| Loans held-for-sale
Investments in loans
Carrying Value	$ 285,808	$ 90,332
Face Amount	$ 278,736	$ 90,789
Weighted Average Life	9 years 8 months 12 days	10 years
CMBS, fair value option \| Loans held-for-sale \| Weighted-average
Investments in loans
Weighted Average Coupon	3.60%	3.90%
First mortgage loan participation \| Loans held for investment
Investments in loans
Carrying Value	$ 10,984,936	$ 8,931,772
Face Amount	$ 11,043,211	$ 8,978,373
Weighted Average Life	1 year 9 months 18 days	1 year 6 months
First mortgage loan participation \| Loans held for investment \| Weighted-average
Investments in loans
Weighted Average Coupon	4.90%	5.30%
Subordinated mortgages \| Loans held for investment
Investments in loans
Carrying Value	$ 81,159	$ 71,185
Face Amount	$ 82,916	$ 72,257
Weighted Average Life	3 years	2 years 9 months 18 days
Subordinated mortgages \| Loans held for investment \| Weighted-average
Investments in loans
Weighted Average Coupon	9.60%	8.80%
Mezzanine Loans
Investments in loans
Total net loans	$ 1,200,000	$ 877,300
Mezzanine Loans \| Loans held for investment
Investments in loans
Carrying Value	477,227	620,319
Face Amount	$ 474,105	$ 619,352
Weighted Average Life	1 year 3 months 18 days	1 year 7 months 6 days
Mezzanine Loans \| Loans held for investment \| Weighted-average
Investments in loans
Weighted Average Coupon	9.60%	10.10%
Other \| Loans held for investment
Investments in loans
Carrying Value	$ 17,689	$ 30,284
Face Amount	$ 19,450	$ 33,626
Weighted Average Life	2 years 3 months 18 days	1 year 9 months 18 days
Other \| Loans held for investment \| Weighted-average
Investments in loans
Weighted Average Coupon	8.20%	8.90%
Residential loans, fair value option \| Loans held for investment
Investments in loans
Carrying Value	$ 91,499	$ 90,684
Face Amount	$ 91,280	$ 86,796
Residential loans, fair value option \| Loans held for investment \| Weighted-average
Investments in loans
Weighted Average Coupon	6.10%	6.00%
Residential loans, fair value option \| Residential Portfolio Segment \| Loans held for investment
Investments in loans
Carrying Value	$ 91,499