Unsecured Debt - Senior Unsecured Notes (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2020	Oct. 31, 2019	Aug. 31, 2019	Mar. 31, 2019	Feb. 28, 2019	Mar. 31, 2018	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2014	Apr. 30, 2013
Debt Instrument [Line Items]
Debt instrument face amount	$ 5,050,000,000	$ 5,350,000,000
Unsecured Bonds 3.250%
Debt Instrument [Line Items]
Debt instrument face amount	$ 0	300,000,000
Unsecured Bonds 3.250% | Senior Notes
Debt Instrument [Line Items]
Coupon Rate	3.25%											3.25%
Unsecured Bonds 3.875%
Debt Instrument [Line Items]
Debt instrument face amount	$ 400,000,000	400,000,000
Unsecured Bonds 3.875% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount											$ 400,000,000
Coupon Rate	3.875%										3.875%
Unsecured Bonds 3.500%
Debt Instrument [Line Items]
Debt instrument face amount	$ 500,000,000	500,000,000
Unsecured Bonds 3.500% | Senior Notes
Debt Instrument [Line Items]
Coupon Rate	3.50%
Unsecured Bonds 3.375%
Debt Instrument [Line Items]
Debt instrument face amount	$ 450,000,000	450,000,000
Unsecured Bonds 3.375% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount										$ 450,000,000
Coupon Rate	3.375%									3.375%
Unsecured Bonds 3.625%
Debt Instrument [Line Items]
Debt instrument face amount	$ 350,000,000	350,000,000
Unsecured Bonds 3.625% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount									$ 350,000,000
Coupon Rate	3.625%								3.625%
Unsecured Bonds 1.700%
Debt Instrument [Line Items]
Debt instrument face amount	$ 450,000,000	450,000,000
Unsecured Bonds 1.700% | Senior Notes
Debt Instrument [Line Items]
Coupon Rate	1.70%
Unsecured Bonds 4.000%
Debt Instrument [Line Items]
Debt instrument face amount	$ 500,000,000	500,000,000
Unsecured Bonds 4.000% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount						$ 150,000,000	$ 350,000,000
Coupon Rate	4.00%						4.00%
Unsecured Bonds 3.000%
Debt Instrument [Line Items]
Debt instrument face amount	$ 550,000,000	550,000,000
Unsecured Bonds 3.000% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount				$ 150,000,000	$ 400,000,000
Coupon Rate	3.00%				3.00%
Unsecured Bonds 1.650%
Debt Instrument [Line Items]
Debt instrument face amount	$ 300,000,000	300,000,000
Unsecured Bonds 1.650% | Senior Notes
Debt Instrument [Line Items]
Coupon Rate	1.65%
Unsecured Bonds 2.550%
Debt Instrument [Line Items]
Debt instrument face amount	$ 300,000,000	300,000,000
Unsecured Bonds 2.550% | Senior Notes
Debt Instrument [Line Items]
Coupon Rate	2.55%
Unsecured Bonds 2.650%
Debt Instrument [Line Items]
Debt instrument face amount	$ 650,000,000	650,000,000
Unsecured Bonds 2.650% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount			$ 150,000,000
Coupon Rate	2.65%
Unsecured Bonds 4.500%
Debt Instrument [Line Items]
Debt instrument face amount	$ 300,000,000	300,000,000
Unsecured Bonds 4.500% | Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount								$ 300,000,000
Coupon Rate	4.50%							4.50%
Unsecured Bonds 2.650%
Debt Instrument [Line Items]
Debt instrument face amount	$ 300,000,000	$ 300,000,000
Unsecured Bonds 2.650% | Senior Notes
Debt Instrument [Line Items]
Coupon Rate	2.65%