Description of the Business and Summary of Significant Accounting Policies - ASU 2016-02 (Details) - Accounting Standards Update 2016-02 [Member] - Scenario, Forecast [Member] $ in Millions	Jan. 01, 2019 USD ($)
Minimum [Member]
Assets and Liabilities, Lessee [Abstract]
Right-of-use asset	$ 95
Lease liability	95
Maximum [Member]
Assets and Liabilities, Lessee [Abstract]
Right-of-use asset	105
Lease liability	105
Expected net impact to assets and liabilities	$ 5