The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
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No definition available.

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Mortgage Servicing Rights and Related Liabilities - Narrative (Details) - USD ($)	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Servicing Asset at Amortized Cost [Line Items]
UPB	$ 277,975,000,000	$ 296,782,000,000
Forward MSRs Sold
Servicing Asset at Amortized Cost [Line Items]
UPB	71,000,000		$ 22,932,000,000
Forward MSRs Sold, Subservicing Retained
Servicing Asset at Amortized Cost [Line Items]
UPB	0		$ 20,560,000,000
Reverse Mortgage Servicing Rights
Servicing Asset at Amortized Cost [Line Items]
Impairment	0
Mortgage servicing rights
Servicing Asset at Amortized Cost [Line Items]
UPB	277,975,000,000	296,782,000,000
HECM
Servicing Asset at Amortized Cost [Line Items]
UPB	$ 20,758,000,000	$ 22,725,000,000