Equity - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 31, 2020	Mar. 31, 2019	Aug. 31, 2018	Jul. 31, 2016
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	8,000,000.0
Preferred stock, shares issued (in shares)	0	0	0
Preferred stock, shares outstanding (in shares)	0	0	0
Payments for repurchase of common stock	$ 6,679,100,000	$ 5,868,300,000	$ 4,352,600,000
Series A
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1,750,000
Series X junior participating
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1,000,000.0
Undesignated
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	5,250,000
2020 Share Repurchase Program
Class of Stock [Line Items]
Authorized amount of share repurchases				$ 5,000,000,000.0
Repurchase of common stock, at cost (in shares)	1,600,000
Payments for repurchase of common stock	$ 400,000,000.0
December 2019 Share Repurchase Program
Class of Stock [Line Items]
Authorized amount of share repurchases		$ 5,000,000,000.0
Repurchase of common stock, at cost (in shares)	16,700,000
Payments for repurchase of common stock	$ 5,000,000,000.0
March 2019 Share Repurchase Program
Class of Stock [Line Items]
Authorized amount of share repurchases					$ 5,000,000,000.0
Repurchase of common stock, at cost (in shares)	4,100,000	14,700,000
Payments for repurchase of common stock	$ 1,300,000,000	$ 3,700,000,000
2018 Share Repurchase Program
Class of Stock [Line Items]
Authorized amount of share repurchases						$ 3,500,000,000
Repurchase of common stock, at cost (in shares)		8,900,000	4,300,000
Payments for repurchase of common stock		$ 2,100,000,000	$ 1,400,000,000
2016 Share Repurchase Program
Class of Stock [Line Items]
Authorized amount of share repurchases							$ 5,000,000,000.0
Repurchase of common stock, at cost (in shares)			10,500,000
Payments for repurchase of common stock			$ 3,000,000,000.0