Summary of Significant Accounting Policies - Narrative (Details) $ in Billions	Jan. 01, 2019 USD ($)
ASU No. 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stranded tax effects in AOCI elected not to reclassify	$ 1.2

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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