Debt Obligations (0.875% Senior Unsecured Notes Due 2030) (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
Feb. 29, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Net proceeds from senior note		$ 1,928
Increase (decrease) in carrying amount		$ 1,353
3.875% senior unsecured notes repaid on March 16, 2020
Debt Instrument [Line Items]
Stated rate		3.875%
0.875% senior unsecured notes due February 13, 2030
Debt Instrument [Line Items]
Stated rate		0.875%
Senior Notes \| 0.875% Senior Unsecured Notes Due 2030
Debt Instrument [Line Items]
Stated rate		0.875%
Senior Notes \| 3.875% senior unsecured notes repaid on March 16, 2020
Debt Instrument [Line Items]
Stated rate		3.875%
Net proceeds from senior note		$ 0
Increase (decrease) in carrying amount		671
Senior Notes \| 0.875% senior unsecured notes due February 13, 2030
Debt Instrument [Line Items]
Net proceeds from senior note	$ 644	644
Increase (decrease) in carrying amount		$ (52)

Payments (Accretions) And Other of Long-term Debt

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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