Employee Benefit Plans - Schedule of Pre-Tax Amounts in Accumulated Other Comprehensive Income That Are Expected to be Recognized of Net Periodic Benefit Cost (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Defined Pension Benefits
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year [Abstract]
Prior service cost	$ 0
Net actuarial gain (loss)	(1)
Net gain (loss)	(1)
Other Postretirement Benefits
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year [Abstract]
Prior service cost	0
Net actuarial gain (loss)	5
Net gain (loss)	$ 5