Debt - Narrative (Details) - USD ($)	1 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Commercial paper	$ 240,000,000	$ 240,000,000
Repayments of senior notes		9,000,000	$ 384,000,000
Commercial Paper
Debt Instrument [Line Items]
Borrowing capacity	4,000,000,000.0	4,000,000,000.0
Available borrowing capacity	3,800,000,000	$ 3,800,000,000
Senior Notes due June 1, 2024
Debt Instrument [Line Items]
Debt redemption	8,000,000
Repayments of senior notes	$ 9,000,000

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.

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Face (par) amount of debt instrument at time of issuance.

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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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Gross amount of debt extinguished.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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-Publisher FASB
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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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