Long-Term Debt Issuances and Retirements (Details 1) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014
3.9% Senior Unsecured Notes due 2025 [Member] | Williams Partners L.P. [Member]
Debt Instrument [Line Items]
Long-term debt face amount	$ 750
Long-term debt interest rate	3.90%
4.9% Senior Unsecured Notes due 2045 [Member] | Williams Partners L.P. [Member]
Debt Instrument [Line Items]
Long-term debt face amount	500
Long-term debt interest rate	4.90%
4.55% Senior Unsecured Notes due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt face amount	1,250
Long-term debt interest rate	4.55%
5.75% Senior Unsecured Notes due 2044 [Member]
Debt Instrument [Line Items]
Long-term debt face amount	650
Long-term debt interest rate	5.75%
4.3% Senior Unsecured Notes due 2024 [Member] | Williams Partners L.P. [Member]
Debt Instrument [Line Items]
Long-term debt face amount	1,000
Long-term debt interest rate	4.30%
5.4% Senior Unsecured Notes due 2044 [Member] | Williams Partners L.P. [Member]
Debt Instrument [Line Items]
Long-term debt face amount	$ 500
Long-term debt interest rate	5.40%