Amount of short-term and long-term debt and lease obligation.

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Publisher FASB
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Total interest costs incurred during the period and either capitalized or charged against earnings.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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- Definition

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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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
Debt (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 3,500	$ 1,500	$ 5,500
Proceeds from Debt, Net of Issuance Costs	$ 5,442	3,454	1,451
Interest Costs Incurred				867	$ 624	$ 541
Interest Paid, Including Capitalized Interest, Operating and Investing Activities				973	616	$ 527
Total debt				27,302	$ 13,847
Customer Financing [Member]
Debt Instrument [Line Items]
Customer Financing Asset Used For Collateralizing Debt				186
Secured Debt [Member]
Debt Instrument [Line Items]
Total debt				37
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Available amount under credit facility				$ 9,600
364-day Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt maturity date				Oct. 31, 2020
Available amount under credit facility				$ 3,200
Five Year Credit Facility [Member] \| Three Year Expiration [Member]
Debt Instrument [Line Items]
Debt maturity date				Oct. 31, 2022
Five Year Credit Facility [Member] \| Five Year Expiration [Member]
Debt Instrument [Line Items]
Debt maturity date				Oct. 31, 2024
Available amount under credit facility				$ 3,200
Three Year Credit Facility [Member] \| Three Year Expiration [Member]
Debt Instrument [Line Items]
Available amount under credit facility				3,200
Two Point Eight Percent due on March 1, 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 400
Debt maturity date			Mar. 01, 2024
Debt Instrument, Interest Rate, Stated Percentage			2.80%
Three Point Eight Two Five Percent due on March 1, 2059 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 300
Debt maturity date			Mar. 01, 2059
Debt Instrument, Interest Rate, Stated Percentage			3.825%
Three Point Two Percent due on March 1, 2029 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 600	$ 400
Debt maturity date		Mar. 01, 2029	Mar. 01, 2029
Debt Instrument, Interest Rate, Stated Percentage		3.20%	3.20%
Three Point Five Percent due on March 1, 2039 [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 400
Debt maturity date			Mar. 01, 2039
Debt Instrument, Interest Rate, Stated Percentage			3.50%
Two Point Seven Percent due on May 1, 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 600
Debt maturity date		May 01, 2022
Debt Instrument, Interest Rate, Stated Percentage		2.70%
Three Point One Percent Due May 1, 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 650
Debt maturity date		May 01, 2026
Debt Instrument, Interest Rate, Stated Percentage		3.10%
Three Point Six Percent Due May 1, 2034 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 850
Debt maturity date		May 01, 2034
Debt Instrument, Interest Rate, Stated Percentage		3.60%
Three Point Nine Percent Due May 1, 2049 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 800
Debt maturity date		May 01, 2049
Debt Instrument, Interest Rate, Stated Percentage		3.90%
Two Point Three Percent due on August 1, 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 750
Debt maturity date	Aug. 01, 2021
Debt Instrument, Interest Rate, Stated Percentage				2.30%
Two Point Seven Percent due on February 1, 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 1,000
Debt maturity date	Feb. 01, 2027
Debt Instrument, Interest Rate, Stated Percentage				2.70%
Two Point Nine Five Percent due on February 1, 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 750
Debt maturity date	Feb. 01, 2030
Debt Instrument, Interest Rate, Stated Percentage				2.95%
Three Point Two Five Percent due on February 1, 2035 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 750
Debt maturity date	Feb. 01, 2035
Debt Instrument, Interest Rate, Stated Percentage				3.25%
Three Point Seven Five Percent due on February 1, 2050 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 1,250
Debt maturity date	Feb. 01, 2050
Debt Instrument, Interest Rate, Stated Percentage				3.75%
Three Point Nine Five Percent due on August 1, 2059 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 1,000
Debt maturity date	Aug. 01, 2059
Debt Instrument, Interest Rate, Stated Percentage				3.95%