Acquisitions and Divestitures (Detail) (USD $) In Millions, except Share data, unless otherwise specified			12 Months Ended					12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Issuance of Equity [Member]	Dec. 31, 2011 Dividend Declared [Member]	Dec. 31, 2009 Endeavor Gathering LLC Acquisition [Member]	Dec. 31, 2011 Watco Companies, LLC Acquisition [Member]	Dec. 31, 2010 Watco Companies, LLC Acquisition [Member]	Dec. 31, 2011 Deeprock North, LLC Joint Venture [Member] Y bbl acre	Dec. 31, 2010 Kinderhawk Equity Method Acquisition [Member]	Dec. 31, 2011 Watco Companies, LLC 2nd Acquisition [Member]	Dec. 31, 2010 Cypress Interstate Pipeline LLC Divestiture [Member]	Dec. 31, 2011 Megafleet Towing Co., Inc. Assets Divestiture [Member]	Dec. 31, 2011 River Consulting, LLC and Devco USA L.L.C. Divestiture [Member]	Dec. 31, 2011 Arrow Terminals BV [Member]	Dec. 31, 2011 Tgs Development L P Terminal Acquisition [Member] Y T	Dec. 31, 2009 Megafleet Towing Co., Inc. Assets [Member]	Dec. 31, 2009 Portland Airport Pipeline [Member] mi	Dec. 31, 2009 Crosstex Energy Lp Natural Gas Treating Business [Member]	Dec. 31, 2010 Y	Dec. 31, 2010 Slay Industries Terminal Acquisition [Member] acre Y	Dec. 31, 2010 Direct Fuels Terminal Acquisition [Member]	Dec. 31, 2010 Gas-Chill, Inc. Natural Gas Treating Assets [Member] M	Dec. 31, 2010 Allied Concrete Terminal Acquisition [Member] T acre	Dec. 31, 2010 Chevron Refined Products Terminals [Member] bbl	Dec. 31, 2010 Mission Valley California Products Terminal [Member] bbl	Dec. 31, 2011 KinderHawk Field Services and Eaglehawk Field Services [Member] mi Y	Dec. 31, 2010 KinderHawk Field Services and Eaglehawk Field Services [Member]	Dec. 31, 2011 SouthTex Treaters, Inc Acquisition [Member]	Dec. 31, 2011 Lorton, Virginia Products Terminal [Member] bbl acre	Dec. 31, 2011 BOSTCO [Member] bbl
Business Acquisition [Line Items]
Acquisition date															2011-06-10		2009-07-31	2009-10-01	2010-01-15	2010-03-05	2010-07-22	2010-09-01	2010-10-01	2010-10-01	2010-03-01	2011-07-01		2011-11-30	2011-12-15
Purchase price															$ 74.1	$ 21.7	$ 9.0	$ 270.7	$ 201.1	$ 101.6	$ 16.0	$ 13.1	$ 8.6	$ 32.3	$ 13.5	$ 912.1		$ 178.5	$ 12.5
Portion of the purchase price assigned to current assets																		15.0								35.5		26.8
Portion of the purchase price assigned to property, plant and equipment															42.6	7.1	9.0	181.7	43.1	67.9	5.3	8.0	3.9	32.1	13.5	641.6		9.3	12.5	26.1
Portion of the purchase price assigned to deferred charges and other assets															31.5	4.0		25.4	100.0	32.8		5.1	4.7	0.2		140.8		16.7
Portion of the purchase price allocated to goodwill																10.6		48.6	58.0	0.9	10.7					94.2		125.7
Portion of allocated goodwill that is expected to be tax deductible																5.0		48.6
Portion of purchase price allocated to other current assets, deferred charges and other assets																			5.4
Portion of purchase price allocated to long-term investments																				8.2
Cash consideration given (included in total purchase price)															42.9	18.0		265.3	114.3	97.0	15.9	10.5	8.1	31.5	13.5	835.1		151.5
Fair value at acquisition date of equity interests issued (included in total purchase price)															23.7				81.7
Fair value at acquisition date of liabilities assumed (included in total purchase price)																		5.4	5.1	1.6	0.1		0.5	0.8		77.0		27.0
Storage capacity acquired (in barrels)																								650,000	170,000				450,000
Number of marine vessels acquired (in vessels)																9
Length of pipeline acquired (in miles)																	8.5									400.0
Diameter of pipeline acquired (in inches)																	8
Number of natural gas amine-treating and dew-point control plants acquired (in plants)																		290
Number of acres ready for development (in acres)																				175
Length of time after closing within which the holdback amount must be paid (in months)																						18
Acres of land acquired (in acres)																							42						14
Tons of material capacity (in tons)															1,000,000								250,000
Estimated time subsequent to close when liability will be paid (in years)															1
Portion of the purchase price assigned to other intangible assets															31.5				94.6	24.6						883.2		0.1
Remaining useful life of intangible assets acquired (in years)																			10	20						20
Date contingent consideration is to be paid																Apr. 23, 2009
Fair value of contingent consideration																3.7
Additional consideration to be paid through 2019																				3.0
Consideration expected to be paid in first half of 2013																				2.0
Amount of consideration holdback to be paid in subsequent period																						2.6
Percent of holdback paid in 2011																						50.00%
Number of mechanical refrigeration units acquired																						100
Date of initial equity investment																														Nov. 08, 2011
Percent of equity acquired in initial investment																											50.00%			50.00%
Cash portion of consideration given for initial equity investment																														11.6
Predevelopment costs paid in 2010																														0.4
Contribution made to equity investment																														6.0
Date of controlling interest purchase																														Dec. 29, 2011
Percent of additional equity interest purchased																														50.00%
Cash consideration for second equity purchase																														8.1
Cash acquired in acquisition																														9.9
Percent of entity Transmontaigne has transferrable purchase option for																														50.00%
Expiration date of purchase option																														Jan. 20, 2013
Value of terminal to be constructed																														430
Number of tanks to be constructed																														52
Storage capacity of tanks to be constructed (in barrels)																														6,600,000
Draft depth of ships entity will be capable of handling (in feet)																														45
Portion of purchase price allocated to Accounts, notes and interest receivable, net																												13.5
Portion of purchase price allocated to inventories																												13.3
Portion of purchase price allocated to deferred charges																												16.6
Pipeline capacity (in bcf)																										2.0
Current gathering volumes (in bcf)																										1.1
Percent ownership of EagleHawk Field Services owned by Petrohawk																										75.00%
EagleHawk length of gathering line (in miles)																										280
EagleHawk length of condensate line (in miles)																										140
Combined fair value of net assets acquired																										1,560.9
Value assigned to equity method investment in EagleHawk																										93.4
Debt of acquired entity paid off as part of acquisition																										154.0
Carrying value of equity method investment at time of write down																										910.2
Fair value of equity investment at time of write down																										743.0
Percentage of EagleHawk's equity acquired																										25.00%
Percent of equity acquired in second step of acquisition																										50.00%
Non-cash loss on remeasurement of previously held equity interest																										167.2
Note issued as consideration in acquisition															7.5
Date to which Petrohawk continued to operate EagleHawk																											Oct. 01, 2010
Portion of purchase price assigned to accounts, notes and interest receivable, net																										16.6
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from disposal of assets											10.2	4.1		13.3
Gain (loss) on disposal											8.8	2.2
Loss resulting from write down of net assets												5.5
Loss, net of tax, resulting from write down of net assets												4.1
Reduction in income tax expense included in gain on sale of assets												1.9
Ownership interest divested (in hundredths)											50.00%	51.00%	51.00%
Number of subsidiaries divested in the disposal transaction													2.0
Aggregate consideration received													8.1
Cash proceeds from divestiture of partial interest in formerly consolidated subsidiaries													1.0
Ownership interest retained (in hundredths)												49.00%	49.00%
Investment in net assets at time of disposal											20.0		8.8
Carrying value of retained investment after remeasurement to fair value											18.6
Carrying value of retained investment before remeasurement to fair value											10.0
Date of sale											Oct. 01, 2010	Feb. 09, 2011	Apr. 01, 2011	Aug. 31, 2011
Tax expense related to gain													1.4
Receivable for settlement of working capital													3.0
Pre tax gain on sale													3.6	1.3
Gain on remeasurement to fair value											8.6		2.1
Note received as consideration for equity interests sold													4.1
Goodwill removed from balance sheet at time of sale												10.6
Schedule of Equity Method Investments - Acquisitions [Line Items]
Acquisition date					Nov. 01, 2009	Jan. 03, 2011		Feb. 17, 2011	May 21, 2010	Dec. 28, 2011
Number of Class A preferred shares acquired (in shares)						50,000				50,000
Equity investment purchase price					36.0	50.0		15.9	917.4	50.0
Interest rate, per quarter, for cash distributions from the preferred shares (in hundredths)						3.25%				3.25%
Interest rate applicable to additional profit distributions from the preferred shares (in hundredths)						0.50%				0.50%
Number of members of the Board of Managers that the Company has the right to appoint						1
Amount reserved for investment in a cash escrow account, included in restricted deposits at year end	0	50.0					50.0
Net equity investment at end of period	3,338.0	3,877.8								101.7
Number of short line railroads operated by the investee						22
Length of leased and owned track on which the short line railroads of the investee operate (in miles)						3,500
Equity investment percentage of business purchased (in hundredths)					40.00%			50.00%	50.00%
Storage capacity of existing crude oil tank farm (in millions of barrels)								1
Incremental storage capacity to be provided by new storage tanks (in barrels)								750,000
Member interest in joint venture owned by Deeprock Energy Resources, LLC (in hundredths)								12.02%
Member interest in joint venture owned by Mecuria Energy Trading, Inc. (in hundredths)								37.98%
Minimum number of years for which Mecuria will remain the anchor tenant for the joint venture's crude oil capacity								5
Number of acres of undeveloped land for which the Company has an option to participate in future expansions								254
Portion of purchase price attributable to equity method goodwill									144.8
Co-venturer ownership interest in joint venture (in hundredths)					60.00%
Annual rate of preferred distributions from equity investment						13.00%				13.00%
Amount included in Deferred Charges and Other					36.0	50.0		15.9	917.4	50.0
Contribution to joint venture made subsequent to initial investment								7.7
Subsequent Event [Line Items]
Date of subsequent event				Jan. 18, 2012
Gain (loss) on transaction											8.8	2.2
Number of units issued subsequent to period end			160,510
Commissions paid on units issued subsequent to period end			0.1
Net proceeds on sales of units subsequent to period end			$ 13.4
Amount of distribution occurring subsequent to period end, per unit				$ 1.16
Ownership interest acquired (in hundredths)	50.20%