REPORTABLE SEGMENTS (Financial information by segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenues from external customers	$ 1,819,452	$ 1,715,316	$ 1,628,095	$ 1,687,577	$ 1,454,496	$ 1,290,644	$ 1,267,706	$ 1,871,981	$ 6,850,440	$ 5,884,827	$ 5,417,295
Costs of products sold									4,189,353	3,599,941	3,122,056
Depreciation and amortization									430,904	343,011	312,803
Segment Adjusted EBITDA									1,742,563	1,540,888	1,477,390
Interest expense, net of interest capitalized									(474,113)	(412,553)	(394,274)
Gains (losses) on non-hedged interest rate derivatives									(77,409)	4,616	39,239
Income tax expense									(18,815)	(15,536)	(12,777)
Non-cash compensation expense									(37,457)	(28,430)	(25,282)
Allowance for equity funds used during construction									957	28,942	10,557
Unrealized gains (losses) on commodity risk management activities									(11,407)	(78,300)	29,980
Impairments of investments in affiliate									(5,355)	(52,620)	0
Losses on disposal of assets									(3,188)	(5,043)	(1,564)
Adjusted EBITDA attributable to noncontrolling interest									37,842	0	0
Proportionate share of unconsolidated affiliates' interest, depreciation and allowance for equity funds used during construction									(29,994)	(22,499)	(22,331)
Other, net									4,442	(482)	2,157
Net income	217,294	76,050	156,616	247,202	226,881	107,387	42,843	240,111	697,162	617,222	791,542
Net Income (Loss) Attributable to Noncontrolling Interest									28,188	0	0
Net income attributable to partners									668,974	617,222	791,542
Assets	15,518,616				12,149,992				15,518,616	12,149,992	11,734,972
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									2,921,865	1,470,001	680,780
Intrastate transportation and storage [Member]
Revenues from external customers									2,397,887	2,075,217	1,773,528
Intersegment revenues									276,270	1,215,688	618,016
Revenue total									2,674,157	3,290,905	2,391,544
Costs of products sold									1,774,006	2,381,397	1,393,295
Depreciation and amortization									119,600	116,992	107,605
Segment Adjusted EBITDA									667,294	716,176	768,934
Assets	4,784,630				4,894,352				4,784,630	4,894,352	4,901,102
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									52,388	117,295	378,494
Interstate transportation [Member]
Revenues from external customers									446,743	292,419	270,213
Depreciation and amortization									80,839	52,582	48,297
Segment Adjusted EBITDA									373,409	220,027	228,705
Assets	3,661,098				3,390,588				3,661,098	3,390,588	3,313,837
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									207,962	872,112	99,341
Midstream [Member]
Revenues from external customers									2,041,600	1,955,627	2,060,451
Intersegment revenues									551,783	1,213,687	380,709
Revenue total									2,593,383	3,169,314	2,441,160
Costs of products sold									2,085,951	2,759,113	2,116,279
Depreciation and amortization									111,226	85,942	70,845
Segment Adjusted EBITDA									388,578	329,025	206,232
Assets	2,665,610				1,842,370				2,665,610	1,842,370	1,523,538
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									836,841	404,669	95,081
NGL Transportation And Services [Member] [Member]
Revenues from external customers									362,701	0	0
Intersegment revenues									34,400	0	0
Revenue total									397,101	0	0
Costs of products sold									218,283	0	0
Depreciation and amortization									32,459	0	0
Segment Adjusted EBITDA									88,197	0	0
Assets	2,360,095				0				2,360,095	0	0
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									1,745,035	0	0
Retail Propane [Member]
Revenues from external customers									1,468,082	1,419,646	1,292,583
Costs of products sold									860,323	774,742	596,002
Depreciation and amortization									82,310	81,947	83,476
Segment Adjusted EBITDA									222,204	269,670	270,027
Assets	1,783,770				1,791,254				1,783,770	1,791,254	1,784,353
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									66,053	64,520	62,953
All Other[Member]
Revenues from external customers									133,427	141,918	20,520
Intersegment revenues									54,155	145,405	1,145
Revenue total									187,582	287,323	21,665
Costs of products sold									155,374	235,614	16,350
Depreciation and amortization									4,470	5,548	2,580
Segment Adjusted EBITDA									2,881	5,990	3,492
Assets	263,413				231,428				263,413	231,428	212,142
Additions to property, plant and equipment including acquisitions, net of contributions in aid of construction costs (accrual basis)									13,586	11,405	44,911
Intersegment Elimination [Member]
Revenue total									(916,608)	(2,574,780)	(999,870)
Costs of products sold									(904,584)	(2,550,925)	(999,870)
Employee [Member]
Non-cash compensation expense										$ (27,180)	$ (24,032)