Subsequent Events (Details) - Subsequent Event - USD ($) $ / shares in Units, shares in Millions	Feb. 21, 2019	Feb. 08, 2019	Feb. 19, 2019
Subsequent Event [Line Items]
Stock repurchase program, authorized amount		$ 500,000,000
Stock repurchase program, additional amount authorized		$ 500,000,000
Minimum
Subsequent Event [Line Items]
Dividends payable, planned decrease (USD per share)		$ 0.06
Maximum
Subsequent Event [Line Items]
Dividends payable, planned decrease (USD per share)		$ 0.02
Accelerated Share Repurchase Program
Subsequent Event [Line Items]
Stock repurchase program, authorized amount			$ 700,000,000
Initial number of shares received	32