Contractual interest rate for funds borrowed, under the debt agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt and Credit Facilities - Term Loan Facilities (Details) - USD ($)	1 Months Ended	12 Months Ended
	Oct. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017
Term Loan Facilities
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 6,000,000,000
Proceeds from Lines of Credit	$ 6,000,000,000
Interest Rate		1.85%
Repayments of Lines of Credit		$ 4,500,000,000	$ 1,500,000,000
364-day senior unsecured term loan facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				1,000,000,000.0
Three-year senior unsecured term loan facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				2,500,000,000.0
Five-year senior unsecured term loan facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 2,500,000,000.0