Transactions with Affiliates (Details Textual) (USD $)	3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended		1 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2013 employee	Sep. 30, 2012	Sep. 30, 2013 employee	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Affiliated Entity [Member]	Sep. 30, 2012 Affiliated Entity [Member]	Sep. 30, 2013 Affiliated Entity [Member]	Sep. 30, 2012 Affiliated Entity [Member]	Sep. 30, 2013 Williams Partners L.P. [Member]	Dec. 31, 2012 Williams Partners L.P. [Member]	Sep. 30, 2013 Williams Field Services Company [Member]	Sep. 30, 2012 Williams Field Services Company [Member]	Sep. 30, 2013 Williams Field Services Company [Member]	Sep. 30, 2012 Williams Field Services Company [Member]	Oct. 31, 2013 Williams Partners Operating LLC [Member]	Sep. 30, 2013 Williams Partners Operating LLC [Member]	Sep. 30, 2012 Williams Partners Operating LLC [Member]	Sep. 30, 2013 The Williams Companies, Inc.[Member]	Sep. 30, 2012 The Williams Companies, Inc.[Member]	Sep. 30, 2013 The Williams Companies, Inc.[Member]	Sep. 30, 2012 The Williams Companies, Inc.[Member]
Related Party Transaction [Line Items]
Advances to affiliate	$ 470,953,000		$ 470,953,000		$ 312,165,000					$ 471,000,000	$ 312,200,000
Related Party Transaction, Rate			0.01%
Total operating revenues	332,255,000	302,957,000	1,006,196,000	906,600,000		1,600,000	7,500,000	14,100,000	8,600,000
Cost of natural gas sales	27,282,000	15,828,000	87,866,000	36,691,000		1,700,000	800,000	5,700,000	3,200,000
Entity Number of Employees	0		0
RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty																			79,500,000	81,200,000	233,000,000	238,700,000
Total operating costs and expenses	(235,248,000)	(231,945,000)	(696,471,000)	(678,640,000)								600,000	1,100,000	1,700,000	2,700,000
Cash distributions to parent			186,000,000	196,259,000												64,000,000	186,000,000	196,300,000
Cash contributions from parent			$ 203,000,000	$ 117,000,000												$ 61,000,000	$ 203,000,000	$ 117,000,000