Summary of Significant Accounting Policies (Details) - Accounting Standards Update 2016-02 $ in Millions	Dec. 31, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 36
Lease liabilities	$ 42

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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