Accounting Pronouncements Accounting Pronouncements (Details) - USD ($) $ in Millions		9 Months Ended
Jan. 01, 2020	Sep. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Credit Losses, Topic 326 (ASC Topic 326)		$ 2
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Credit Losses, Topic 326 (ASC Topic 326)	$ 2	$ 2

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.

No definition available.

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