Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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(13)(2))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 944
-SubTopic 210
-Section S99
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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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Amount of increase (decrease), classified as other, of the credit facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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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.

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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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Debt - Line of Credit and Commercial Paper - Schedule of Unsecured Revolving Credit Facility (Details) - USD ($)	6 Months Ended
	Jun. 30, 2020	Nov. 04, 2019	Nov. 03, 2019	Nov. 01, 2019	Oct. 31, 2019
Line of Credit Facility [Line Items]
Commercial paper balance outstanding	$ (1,000,000,000.0)	$ (1,000,000,000.0)	$ (500,000,000.0)
Unsecured Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Unsecured revolving credit facility commitment	2,500,000,000			$ 2,500,000,000	$ 2,000,000,000.0
Other restricted amounts	(100,949,000)
Unsecured revolving credit facility availability	$ 2,399,051,000