Debt and Finance Lease Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt and Finance Lease Obligations:
Net unamortized debt issuance costs and other	$ (88)	$ (80)
Total debt	8,881	8,503
Finance lease obligations (see Note 5)	791
Finance lease obligations (see Note 5)		606
Total debt and finance lease obligations	9,672	9,109
Less: Current portion	494	238
Debt and finance lease obligations, less current portion	9,178	8,871
Credit Facilities [Member] \| Canadian Revolver [Member]
Short-term Debt [Line Items]
Short-term debt at stated values	0	0
Credit Facilities [Member] \| Accounts Receivable Sales Facility [Member]
Short-term Debt [Line Items]
Short-term debt at stated values	100	100
Credit Facilities [Member] \| Valero Revolver [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	0	0
Credit Facilities [Member] \| IEnova Revolver [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	348	109
Senior Notes [Member] \| 6.625% Valero Senior Notes Due in 2037 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 1,500	1,500
Interest rate of notes (percent)	6.625%
Senior Notes [Member] \| 3.4% Valero Senior Notes Due in 2026 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 1,250	1,250
Interest rate of notes (percent)	3.40%
Senior Notes [Member] \| 4.0% Valero Senior Notes Due in 2029 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 1,000	0
Interest rate of notes (percent)	4.00%
Senior Notes [Member] \| 6.125% Valero Senior Notes Due In 2020 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 0	850
Interest rate of notes (percent)	6.125%
Senior Notes [Member] \| 4.35% Valero Senior Notes Due in 2028 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 750	$ 750
Interest rate of notes (percent)	4.35%	4.35%
Senior Notes [Member] \| 7.5% Valero Senior Notes Due In 2032 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 750	$ 750
Interest rate of notes (percent)	7.50%
Senior Notes [Member] \| 4.9% Valero Senior Notes Due in 2045 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 650	650
Interest rate of notes (percent)	4.90%
Senior Notes [Member] \| 3.65% Valero Senior Notes Due in 2025 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 600	600
Interest rate of notes (percent)	3.65%
Senior Notes [Member] \| 10.5% Valero Senior Notes Due In 2039 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 250	250
Interest rate of notes (percent)	10.50%
Senior Notes [Member] \| 8.75% Valero Senior Notes Due In 2030 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 200	200
Interest rate of notes (percent)	8.75%
Senior Notes [Member] \| 7.45% Valero Senior Notes Due In 2097 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 100	100
Interest rate of notes (percent)	7.45%
Senior Notes [Member] \| 6.75% Valero Senior Notes Due In 2037 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 24	24
Interest rate of notes (percent)	6.75%
Senior Notes [Member] \| 4.375% VLP Senior Notes Due in 2026 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 500	500
Interest rate of notes (percent)	4.375%
Senior Notes [Member] \| 4.5% VLP Senior Notes Due in 2028 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 500	500
Interest rate of notes (percent)	4.50%
Revenue Bonds [Member] \| Gulf Opportunity Zone Revenue Bonds Series 2010, 4.0% [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 300	300
Interest rate of notes (percent)	4.00%
Debentures [Member] \| Debenture, 7.65% Due In 2026 [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 100	100
Interest rate of notes (percent)	7.65%
Other Debt [Member]
Debt Instruments [Abstract]
Long-term debt at stated values	$ 47	$ 50

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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