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

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

+ Details

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448

+ Details

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

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Commercial Mortgage Loans - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			$ 20,886
Provision/(benefit) for credit losses	$ (1,508)	$ 4,042	(3,839)	$ 18,639
Ending Balance	17,192		17,192
Commercial Portfolio Segment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	18,600		20,886
Provision/(benefit) for credit losses	(1,408)		(3,405)
Write offs	0		(289)
Ending Balance	17,192		17,192
Commercial Portfolio Segment \| Multifamily
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,884		3,095
Provision/(benefit) for credit losses	2,505		4,583
Write offs	0		(289)
Ending Balance	7,389		7,389
Commercial Portfolio Segment \| Retail
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	402		404
Provision/(benefit) for credit losses	(299)		(301)
Write offs	0		0
Ending Balance	103		103
Commercial Portfolio Segment \| Office
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,201		1,575
Provision/(benefit) for credit losses	(173)		(547)
Write offs	0		0
Ending Balance	1,028		1,028
Commercial Portfolio Segment \| Industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	608		3,795
Provision/(benefit) for credit losses	(409)		(3,596)
Write offs	0		0
Ending Balance	199		199
Commercial Portfolio Segment \| Mixed Use
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	385		132
Provision/(benefit) for credit losses	55		308
Write offs	0		0
Ending Balance	440		440
Commercial Portfolio Segment \| Manufactured Housing
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	10,873		11,646
Provision/(benefit) for credit losses	(3,158)		(3,931)
Write offs	0		0
Ending Balance	7,715		7,715
Commercial Portfolio Segment \| Self-Storage
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	140		117
Provision/(benefit) for credit losses	101		124
Write offs	0		0
Ending Balance	241		241
Commercial Portfolio Segment \| Manufactured Housing
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	107		122
Provision/(benefit) for credit losses	(30)		(45)
Write offs	0		0
Ending Balance	77		77
Unfunded Loan Commitment \| Commercial Portfolio Segment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	331		665
Provision/(benefit) for credit losses	(100)		(434)
Ending Balance	231		231
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Multifamily
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	153		85
Provision/(benefit) for credit losses	(33)		35
Ending Balance	120		120
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Retail
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	0		0
Provision/(benefit) for credit losses	0		0
Ending Balance	0		0
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Office
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	38		47
Provision/(benefit) for credit losses	(10)		(19)
Ending Balance	28		28
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	101		418
Provision/(benefit) for credit losses	(91)		(408)
Ending Balance	10		10
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Mixed Use
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	12		14
Provision/(benefit) for credit losses	(4)		(6)
Ending Balance	8		8
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Manufactured Housing
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	27		101
Provision/(benefit) for credit losses	38		(36)
Ending Balance	65		65
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Self-Storage
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	0		0
Provision/(benefit) for credit losses	0		0
Ending Balance	0		0
Unfunded Loan Commitment \| Commercial Portfolio Segment \| Manufactured Housing
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	0		0
Provision/(benefit) for credit losses	0		0
Ending Balance	$ 0		$ 0