Equity - Stock Repurchase Activities (Details) $ / shares in Units, shares in Millions										1 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 26, 2019 $ / shares	Oct. 28, 2019 USD ($) $ / shares shares	Oct. 24, 2019 $ / shares	Sep. 25, 2019 $ / shares	Jul. 25, 2019 $ / shares	Jun. 24, 2019 $ / shares	Apr. 25, 2019 $ / shares	Mar. 22, 2019 $ / shares	Jan. 29, 2019 $ / shares	Oct. 31, 2019 USD ($)	Apr. 30, 2019 USD ($)	Feb. 28, 2018 USD ($)	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) Dividend $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Jan. 31, 2018 USD ($)
Dividends
Per Share (in dollars per share) | $ / shares	$ 0.19			$ 0.19		$ 0.19		$ 0.19					$ 0.19		$ 0.76	$ 0.72	$ 0.40
Amount															$ 260,100,000	$ 249,300,000	$ 150,400,000
Stock Repurchase Program
Number of quarterly cash dividends declared | Dividend															4
Cash dividends declared per share of common stock (in dollars per share) | $ / shares			$ 0.19		$ 0.19		$ 0.19		$ 0.19
Payment to repurchase stock															$ 554,900,000	$ 756,600,000	$ 725,800,000
Stock repurchased under ASR, market price (in dollars per share) | $ / shares		$ 25.15
Remaining forward contract, value															$ 40,000,000.0
Stock Repurchase Program 2018
Stock Repurchase Program
Shares (in shares) | shares															20.1	29.3
Average price per share (in dollars per share) | $ / shares															$ 25.36	$ 25.62
Amount		$ 160,000,000.0											$ 50,000,000.0		$ 550,000,000.0	$ 750,000,000.0
Tax Withholding Amount															5,000,000.0	6,600,000
Dividends and stock repurchase program, total amount															815,100,000	$ 1,005,900,000
Stock repurchase program, authorized amount										$ 3,000,000,000.0								$ 2,000,000,000.0
Stock repurchase program, increased amount										$ 1,000,000,000.0
Stock repurchased (in Shares) | shares													2.1
Stock repurchased average cost (in usd per share) | $ / shares													$ 23.63
Stock repurchase program, authorized funds remaining													$ 1,700,000,000	$ 1,700,000,000	$ 1,700,000,000
Stock Repurchase Program 2014
Stock Repurchase Program
Shares (in shares) | shares																	26.1
Average price per share (in dollars per share) | $ / shares																	$ 27.61
Amount																	$ 719,700,000
Tax Withholding Amount																	6,100,000
Dividends and stock repurchase program, total amount																	$ 876,200,000
Accelerated Share Repurchase Program
Stock Repurchase Program
Shares (in shares) | shares		6.4												11.6	29.3
Average price per share (in dollars per share) | $ / shares														$ 25.79	$ 25.62
Stock repurchase program, authorized amount		$ 200,000,000.0
Payment to repurchase stock		$ 200,000,000.0									$ 300,000,000.0	$ 750,000,000.0