Accumulated Unrealized Gain (Loss) on Derivatives

No definition available.

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- Definition

Related Party Transaction Shares Issued

+ References

No definition available.

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- Definition

Securities Sold under Agreements to Repurchase, Guaranteed Balance

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19-26)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of transactions with related party during the financial reporting period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272

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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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- Definition

This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.

+ References

No definition available.

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Related Party Transactions - Narrative (Details) - USD ($)		12 Months Ended
	Jul. 01, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Proceeds from sale of loan	$ 1,000,000,000
Gain on sale		$ 1,439,000,000	$ 1,213,000,000	$ 866,000,000
Available-for-sale Securities		17,789,000,000	16,314,000,000
Increase in retained earnings		(57,000,000)	4,000,000	9,000,000
Liabilities		154,443,000,000	151,520,000,000
Derivative, Notional Amount		241,444,000,000	201,094,000,000
MUSA and Various other Non-Bank Subsidiaries
Related Party Transaction [Line Items]
Derivative, Notional Amount		4,100,000,000	4,000,000,000
Unrealized gains		68,000,000	96,000,000
Unsecured Debt [Member] \| MUSA and Various other Non-Bank Subsidiaries
Related Party Transaction [Line Items]
Unsecured revolving credit facility with BTMU		1,500,000,000
Retained Earnings
Related Party Transaction [Line Items]
Increase in retained earnings		(5,000,000)	0	0
Affiliated Entity [Member] \| MUSA and Various other Non-Bank Subsidiaries
Related Party Transaction [Line Items]
Gain on sale		1,439,000,000	$ 1,213,000,000	$ 866,000,000
Securities sold under agreements to repurchase		0
Sale Of Loans \| Affiliated Entity [Member]
Related Party Transaction [Line Items]
Proceeds from sale of loan		280,000,000
Gain on sale		700,000
Purchase of loans		$ 9,000,000
transfer of goodwill and intangibles [Member]
Related Party Transaction [Line Items]
Proceeds from sale of loan	196,000,000
transfer of liabilities [Member]
Related Party Transaction [Line Items]
Proceeds from sale of loan	$ 601,000,000
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Related Party Transaction Shares Issued	3,267,433