Basis of Presentation and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Estimated Useful Lives Of Property, Plant And Equipment

Depreciation is computed by the straight-line method over the estimated useful lives of the assets, as follows:

	Years
Gathering systems and pipelines	15 - 20
Facilities and equipment	3 - 25
Buildings, rights-of-way and easements	1 - 40
Office furniture and fixtures	5 - 10
Vehicles	5

Intangible Assets, Useful life

Certain intangible assets are amortized on a straight-line basis over their estimated economic lives, as follows:

	Weighted-Average Life (years)
Customer accounts and revenue contracts	20
Trademarks	6 - 8

Intangible assets consisted of the following at December 31, 2017 and 2016 (in millions):

	CEQP				CMLP
	December 31,				December 31,
	2017		2016		2017		2016
Customer accounts	$	438.9	$	541.9	$	438.9	$	541.9
Covenants not to compete	—		1.0		—		1.0
Gas gathering, compression and processing contracts	325.2		325.2		325.2		325.2
Trademarks	24.7		30.5		9.2		15.0
	788.8		898.6		773.3		883.1
Less: accumulated amortization	191.6		241.2		177.6		230.2
Total intangible assets, net	$	597.2	$	657.4	$	595.7	$	652.9

The following table summarizes total accumulated amortization of our intangible assets at December 31, 2017 and 2016 (in millions):

	CEQP				CMLP
	December 31,				December 31,
	2017		2016		2017		2016
Customer accounts	$	89.8	$	162.4	$	89.8	$	162.4
Gas gathering, compression and processing contracts	82.0		63.2		82.0		63.2
Trademarks	19.8		15.6		5.8		4.6
Total accumulated amortization	$	191.6	$	241.2	$	177.6	$	230.2

Schedule of Goodwill

The following table summarizes the goodwill of our various reporting units (in millions):

	Goodwill Impairments during the Year Ended December 31, 2015		Goodwill at January 1, 2016		Goodwill Impairments during the Year Ended December 31, 2016		Other				Goodwill at December 31, 2016		Impact of Sale of US Salt				Goodwill Impairments during the Year Ended December 31, 2017		Goodwill at December 31, 2017
G&P
Fayetteville	$	72.5	$	—	$	—	$	—			$	—	$	—			$	—	$	—
Marcellus	—		8.6		8.6		—				—		—				—		—
Arrow	—		45.9		—		—				45.9		—				—		45.9
S&T
Northeast Storage and Transportation	—		726.3		—		(726.3		)	(1)	—		—				—		—
COLT	623.4		44.9		44.9		—				—		—				—		—
MS&L																			—
West Coast	85.9		—		—		2.4			(2)	2.4		—				2.4		—
Supply and Logistics	99.0		167.2		65.5		—				101.7		—				—		101.7
Storage and Terminals	53.7		50.5		14.1		—				36.4		—				36.4		—
US Salt	—		12.6		—		—				12.6		(12.6		)	(3)	—		—
Trucking	148.4		29.5		29.5		—				—		—				—		—
Watkins Glen	66.2		—		—		—				—		—				—		—
Total CMLP	$	1,149.1	$	1,085.5	$	162.6	$	(723.9	)		$	199.0	$	(12.6	)		$	38.8	$	147.6
Barnett (G&P)	257.2		—		—		—				—		—				—		—
Total CEQP	$	1,406.3	$	1,085.5	$	162.6	$	(723.9	)		$	199.0	$	(12.6	)		$	38.8	$	147.6

(1) Reflects impact of the deconsolidation of our NE S&T assets in June 2016.

(2) In December 2016, we acquired four NGL terminals for our MS&L segment for approximately $7.2 million with total goodwill of approximately $2.4 million. This acquisition was not material to our consolidated financial statements as of and for the year ended December 31, 2016.

(3) In December 2017, we sold 100% of our equity interests in US Salt to an affiliate of Kissner Group Holdings LP.