Intangible Assets, Amortization Expense (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($)
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Three months ended March 31, 2022 (actual)	$ 74
Estimate for the remainder of 2022	231
Estimate for year ended December 31,
2023	269
2024	231
2025	200
2026	160
2027	102
MSRs [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Three months ended March 31, 2022 (actual)	59
Estimate for the remainder of 2022	187
Estimate for year ended December 31,
2023	218
2024	190
2025	167
2026	133
2027	102
Customer relationship and other intangibles [Member]
Finite-Lived Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Three months ended March 31, 2022 (actual)	15
Estimate for the remainder of 2022	44
Estimate for year ended December 31,
2023	51
2024	41
2025	33
2026	27
2027	$ 0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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