Amount of restricted net assets of consolidated and unconsolidated subsidiaries as of the end of the most recently completed fiscal year.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Interest rate stated in the contractual debt agreement.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Debt Leases and Banking Arrangements (Details Textual 2) (USD $)					1 Months Ended
	Dec. 31, 2012	Dec. 31, 2012 Consolidated Entities	Aug. 31, 2011 $375 million (5.4%) due 2041 Unsecured Debt [Member] Transcontinental Gas Pipe Line Company, LLC [Member]	Dec. 31, 2012 $375 million (5.4%) due 2041 Unsecured Debt [Member] Senior Notes [Member] Transcontinental Gas Pipe Line Company, LLC [Member]	Jul. 31, 2012 $325 million (8.875%) due 2012 Unsecured Debt [Member] Transcontinental Gas Pipe Line Company, LLC [Member]	Dec. 31, 2012 $325 million (8.875%) due 2012 Unsecured Debt [Member] Senior Notes [Member] Transcontinental Gas Pipe Line Company, LLC [Member]	Dec. 31, 2012 $400 million (4.45%) due 2042 Unsecured Debt [Member] Senior Notes [Member] Transcontinental Gas Pipe Line Company, LLC [Member]	Jul. 31, 2012 $400 million (4.45%) due 2042 Unsecured Debt [Member] Senior Notes [Member] Transcontinental Gas Pipe Line Company, LLC [Member]	Dec. 31, 2012 $850 million (3.7%) due 2023 Unsecured Debt [Member] Senior Notes [Member] The Williams Companies, Inc.	Dec. 31, 2012 $750 million (3.35%) due 2022 Unsecured Debt [Member] Williams Partners L.P.	Aug. 31, 2012 $750 million (3.35%) due 2022 Unsecured Debt [Member] Senior Notes [Member] Williams Partners L.P.
Debt Instrument [Line Items]
Repayments of Unsecured Debt					$ 325,000,000
Debt Instrument, Interest Rate, Stated Percentage			5.40%	5.40%	8.875%	8.875%	4.45%	4.45%	3.70%	3.35%	3.35%
Debt Instrument, Face Amount			375,000,000					400,000,000	850,000,000		750,000,000
Restrictions for Consolidated and Unconsolidated Subsidiaries [Abstract]
Amount of Restricted Net Assets for Consolidated and Unconsolidated Subsidiaries		$ 6,200,000,000
Restricted Net Assets Threshold	25.00%