Debt and Banking Arrangements (Tables)

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

Long-Term Debt

	December 31,
	2019			2018
	(Millions)
Transco:
7.08% Debentures due 2026	$	8		$	8
7.25% Debentures due 2026	200			200
7.85% Notes due 2026	1,000			1,000
4% Notes due 2028	400			400
5.4% Notes due 2041	375			375
4.45% Notes due 2042	400			400
4.6% Notes due 2048	600			600
Other financing obligation - Atlantic Sunrise	857			807
Other financing obligation - Dalton	259			260
Northwest Pipeline:
7.125% Debentures due 2025	85			85
4% Notes due 2027	500			500
WMB:
4.125% Notes due 2020	600			600
5.25% Notes due 2020	1,500			1,500
4% Notes due 2021	500			500
7.875% Notes due 2021	371			371
3.35% Notes due 2022	750			750
3.6% Notes due 2022	1,250			1,250
3.7% Notes due 2023	850			850
4.5% Notes due 2023	600			600
4.3% Notes due 2024	1,000			1,000
4.55% Notes due 2024	1,250			1,250
3.9% Notes due 2025	750			750
4% Notes due 2025	750			750
3.75% Notes due 2027	1,450			1,450
7.5% Debentures due 2031	339			339
7.75% Notes due 2031	252			252
8.75% Notes due 2032	445			445
6.3% Notes due 2040	1,250			1,250
5.8% Notes due 2043	400			400
5.4% Notes due 2044	500			500
5.75% Notes due 2044	650			650
4.9% Notes due 2045	500			500
5.1% Notes due 2045	1,000			1,000
4.85% Notes due 2048	800			800
Various — 7.625% to 10.25% Notes and Debentures due 2019 to 2027	24			55
Credit facility loans	—			160
Debt issuance costs	(119		)	(131		)
Net unamortized debt premium (discount)	(58		)	(62		)
Total long-term debt, including current portion	22,288			22,414
Long-term debt due within one year	(2,140		)	(47		)
Long-term debt	$	20,148		$	22,367

Schedule of Maturities of Long-term Debt [Table Text Block]

The following table presents aggregate minimum maturities of long-term debt and other financing obligations, excluding net unamortized debt premium (discount) and debt issuance costs, for each of the next five years: 

	December 31, 2019
	(Millions)
2020	$	2,141
2021	893
2022	2,025
2023	1,477
2024	2,279

Schedule of Line of Credit Facilities [Table Text Block]

Credit Facilities

	December 31, 2019
	Stated Capacity		Outstanding
	(Millions)
Long-term credit facility (1)	$	4,500	$	—
Letters of credit under certain bilateral bank agreements			14

________________

(1)

In managing our available liquidity, we do not expect a maximum outstanding amount in excess of the capacity of our credit facility inclusive of any outstanding amounts under our commercial paper program.