Acquisition and Divestiture Activity ( Unaudited Pro Forma Results) (Details) - BBVA USA Bancshares, Inc. - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Net interest income	$ 11,662	$ 12,413
Noninterest income	8,960	7,866
Net income	$ 7,475	$ 4,928

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration