Goodwill (Tables)

12 Months Ended

Dec. 31, 2016

Goodwill And Intangible Assets Disclosure [Abstract]

Changes in Gross Amounts of Goodwill

Changes in the gross amounts of our goodwill are as follows:

	WestTX			SouthTX			SouthOK			Total
Balance at January 1, 2015	$	—		$	—		$	—		$	—
Acquisition, February 27, 2015		364.5			160.3			182.2			707.0
Provisional impairment for 2015 annual assessment		(37.6	)		(70.2	)		(182.2	)		(290.0	)
Balance at December 31, 2015		326.9			90.1			—			417.0
Additional impairment for 2015 annual assessment		(14.4	)		(9.6	)		—			(24.0	)
Impairment for 2016 annual assessment		(137.8	)		(45.2	)		—			(183.0	)
Balance at December 31, 2016	$	174.7		$	35.3		$	—		$	210.0