Leases - Additional Information (Details) $ in Millions	3 Months Ended	12 Months Ended
Jun. 30, 2021 branch	Mar. 31, 2020 branch	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) branch
Leases [Abstract]
Impairment charge			$ 63	$ 76	$ 13
Number of branches closing \| branch	30	60			20
Operating leases, not yet commenced			$ 0

Amount of loss from impairment of right-of-use asset from operating lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 25
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123399704&loc=SL77918431-209957

Name:	us-gaap_OperatingLeaseImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration