Partnership's Calculation of Net Income Per Unit for Common and Subordinated Limited Partner Units (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Earnings Per Unit [Line Items]
Net income attributable to Access Midstream Partners, L.P.	$ 41,218		$ 78,217		$ 169,750		$ 206,968
Less general partner interest in net income	(26,666)		(12,591)		(69,808)		(23,378)
Limited partner interest in net income	14,552		65,626		99,942		183,590
Common Units
Earnings Per Unit [Line Items]
Limited partner interest in net income	5,926	[1]	31,735	[1]	67,183	[1]	64,298	[1]
Subordinated units
Earnings Per Unit [Line Items]
Limited partner interest in net income			11,006				52,564
Class B Units
Earnings Per Unit [Line Items]
Limited partner interest in net income	8,626	[1]	11,044	[1]	28,289	[1]	32,029	[1]
Class C Units
Earnings Per Unit [Line Items]
Limited partner interest in net income			$ 11,841	[1]	$ 4,470	[1]	$ 34,699	[1]
Limited Partner
Weighted average limited partner units outstanding - basic and diluted
Weighted average limited partner units outstanding basic and diluted	191,496,964		178,034,870		188,919,383		174,465,902
Limited Partner | Common Units
Net income per limited partner unit – basic and diluted
Net income per limited partner unit - basic and diluted	$ 0.03		$ 0.22		$ 0.36		$ 0.54
Weighted average limited partner units outstanding - basic and diluted
Weighted average limited partner units outstanding basic and diluted	191,496,964		144,247,636		188,919,383		117,282,006
Limited Partner | Subordinated units
Net income per limited partner unit – basic and diluted
Net income per limited partner unit - basic and diluted			$ 0.33				$ 0.93
Weighted average limited partner units outstanding - basic and diluted
Weighted average limited partner units outstanding basic and diluted			33,787,234				57,183,896

[1] Adjusted to reflect amortization for the beneficial conversion feature.