Long-Term Debt - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended			1 Months Ended	6 Months Ended		1 Months Ended				1 Months Ended			1 Months Ended			6 Months Ended	0 Months Ended			6 Months Ended		1 Months Ended				6 Months Ended									6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Aug. 14, 2013	Mar. 07, 2014 4.875 Percent Senior Notes due March 2024	Jun. 30, 2014 4.875 Percent Senior Notes due March 2024	Dec. 31, 2013 4.875 Percent Senior Notes due March 2024	Aug. 14, 2013 5.875 Percent Senior Notes due April 2021	Apr. 19, 2011 5.875 Percent Senior Notes due April 2021	Jun. 30, 2014 5.875 Percent Senior Notes due April 2021	Dec. 31, 2013 5.875 Percent Senior Notes due April 2021	Dec. 19, 2012 4.875 Percent Senior Notes due May 2023	Jun. 30, 2014 4.875 Percent Senior Notes due May 2023	Dec. 31, 2013 4.875 Percent Senior Notes due May 2023	Jan. 11, 2012 6.125 Percent Senior Notes due July 2022	Jun. 30, 2014 6.125 Percent Senior Notes due July 2022	Dec. 31, 2013 6.125 Percent Senior Notes due July 2022	Jun. 30, 2014 Senior Notes	May 13, 2013 Amended Revolving Credit Facility	May 13, 2013 Swing Line Loan	May 13, 2013 Letter of Credit	Jun. 30, 2014 Maximum	May 13, 2013 Maximum	Mar. 07, 2014 Maximum 4.875 Percent Senior Notes due March 2024	Apr. 19, 2011 Maximum 5.875 Percent Senior Notes due April 2021	Dec. 19, 2012 Maximum 4.875 Percent Senior Notes due May 2023	Jan. 11, 2012 Maximum 6.125 Percent Senior Notes due July 2022	Jun. 30, 2014 Maximum Achieving Investment Grade Status	Jun. 30, 2014 Maximum Libor Plus Rate	Jun. 30, 2014 Maximum London Inter Bank Offered Rate Plus	Jun. 30, 2014 Maximum Eurodollar rate plus a margin	Jun. 30, 2014 Maximum Leverage Based Pricing Grid	Jun. 30, 2014 Maximum Ratings Based Pricing Grid	Jun. 30, 2014 Minimum	Jun. 30, 2014 Minimum Achieving Investment Grade Status	Jun. 30, 2014 Minimum Revolving Credit Facilities	Jun. 30, 2014 Minimum Federal Funds Effective Rate Plus	Jun. 30, 2014 Minimum London Inter Bank Offered Rate Plus	Jun. 30, 2014 Minimum Eurodollar rate plus a margin	Jun. 30, 2014 Minimum Leverage Based Pricing Grid	Jun. 30, 2014 Minimum Ratings Based Pricing Grid	Jun. 30, 2014 Access Midstream Long-Term Incentive Plan	Jun. 30, 2014 Non-Guarantors	Jun. 30, 2014 Guarantor
Line Of Credit Facility [Line Items]
Maturity date of revolving credit facility outstanding amount																				2018-05
Revolving credit facility																				$ 1,750,000,000	$ 100,000,000	$ 200,000,000
Additional borrowing capacity																								2,000,000,000
Borrowing capacity description			The revolving credit facility is secured by all of the Partnership’s assets, and loans thereunder (other than swing line loans) bear interest at the Partnership’s option at either (i) the greater of (a) the reference rate of Wells Fargo Bank, NA, (b) the federal funds effective rate plus 0.50 percent or (c) the Eurodollar rate which is based on the London Interbank Offered Rate (LIBOR), plus 1.00 percent, each of which is subject to a margin that varies from 0.50 percent to 1.50 percent per annum, according to the Partnership’s leverage ratio (as defined in the agreement), or (ii) the Eurodollar rate plus a margin that varies from 1.50 percent to 2.50 percent per annum, according to the Partnership’s leverage ratio.
Commitment fee description			The unused portion of the credit facility is subject to commitment fees of (a) 0.25 percent to 0.375 percent per annum while the Partnership is subject to the leverage-based pricing grid, according to the Partnership’s leverage ratio and (b) 0.15 percent to 0.30 percent per annum while the Partnership is subject to the ratings-based pricing grid, according to its senior unsecured long-term debt ratings.
Debt Instrument variable rate																														1.00%	1.50%	2.50%						0.50%	0.50%	1.50%
Unused credit facility commitment fees																																	0.375%	0.30%							0.25%	0.15%
Outstanding principal amount																																					50,000,000
Leverage ratio																							5.5						5.0						1.0	1.0
Senior Notes issued through private placement						750,000,000			400,000,000				1,400,000,000			750,000,000
Debt, interest rate						4.875%	4.875%	4.875%	5.875%	5.875%	5.875%	5.875%	4.875%	4.875%	4.875%	6.125%	6.125%	6.125%
Debt issuance cost						8,800,000			5,800,000	8,200,000			25,900,000			13,800,000
Net proceeds of additional notes issued									400,800,000
Notes Issued At Price Of Percent Of Principal Amount					101.50%
Proceeds from issuance of private placement										350,000,000
Notes maturity date						Mar. 15, 2024				Apr. 15, 2021			May 15, 2023			Jul. 15, 2022
Interest payable on Senior Notes						March 15 and September 15				April 15 and October 15			May 15 and November 15			January 15 and July 15
Debt redemption date							Mar. 15, 2019			Apr. 15, 2015			Dec. 15, 2017			Jan. 15, 2017									Mar. 15, 2017		Dec. 15, 2015
Debt redemption percentage																									35.00%	35.00%	35.00%	35.00%
Debt redemption description						In addition, the Partnership may redeem up to 35 percent of the 2024 Notes prior to March 15, 2017 under certain circumstances with the net cash proceeds from certain equity offerings.				In addition, the Partnership may redeem up to 35 percent of the 2021 Notes prior to April 15, 2014 under certain circumstances with the net cash proceeds from certain equity offerings.			In addition, the Partnership may redeem up to 35 percent of the 2023 Notes prior to December 15, 2015 under certain circumstances with the net cash proceeds from certain equity offerings.			In addition, the Partnership may redeem up to 35 percent of the 2022 Notes prior to January 15, 2015 under certain circumstances with the net cash proceeds from certain equity offerings.
Senior notes covenants																			The indentures governing the 2024 Notes, the 2023 Notes, the 2022 Notes and the 2021 Notes contain covenants that, among other things, limit the Partnership’s ability and the ability of certain of the Partnership’s subsidiaries to: (1) sell assets including equity interests in its subsidiaries; (2) pay distributions on, redeem or purchase the Partnership’s units, or redeem or purchase the Partnership’s subordinated debt; (3) make investments; (4) incur or guarantee additional indebtedness or issue preferred units; (5) create or incur certain liens; (6) enter into agreements that restrict distributions or other payments from certain subsidiaries to the Partnership; (7) consolidate, merge or transfer all or substantially all of the Partnership’s or certain of the Partnership’s subsidiaries’ assets; (8) engage in transactions with affiliates; and (9) create unrestricted subsidiaries. These covenants are subject to important exceptions and qualifications. If the 2024 Notes, 2023 Notes, 2022 Notes or the 2021 Notes achieve an investment grade rating from either of Moody’s Investors Service, Inc. or Standard & Poor’s Ratings Services and no default, as defined in the indentures, has occurred or is continuing, many of these covenants will terminate.
Percentage of ownership interest																																											100.00%	100.00%	100.00%
Capitalized interest	$ 9,800,000	$ 10,200,000	$ 19,900,000	$ 19,900,000