Variable Interest Entities - Narrative (Details) - Variable Interest Entity, Not Primary Beneficiary $ in Millions	Dec. 31, 2020 USD ($)
Single Asset Leasing Entity
Variable Interest Entity [Line Items]
Maximum Loss Exposure	$ 18
Proprietary Residential Mortgage Securitization Trusts
Variable Interest Entity [Line Items]
Maximum Loss Exposure	$ 1

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121559654&loc=d3e5747-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=121559654&loc=d3e5728-111685

Name:	us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant