Deposit Liabilities (Schedule of Deposit Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Deposits [Abstract]
Noninterest-bearing deposits	$ 167	$ 128
Interest-bearing deposits
Savings, money market, and checking accounts	98,035	83,698
Certificates of deposit	41,242	53,210
Total deposit liabilities	139,444	137,036
Certificates of deposit, $100,000 or more	21,700	25,800
Certificates of deposit, in excess of $250,000 federal insurance limits	$ 7,300	$ 8,600

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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