Principles of Consolidation (Tables)

6 Months Ended

Jun. 30, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

The following table summarizes the fair value hierarchy of our financial assets and liabilities carried at fair value on a recurring basis as of June 30, 2017:

			Fair Value Measurement Hierarchy
(in millions)	Total Carrying Value		Quoted prices in active market (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Restricted amounts held in escrow-current	$	54.0	$	54.0	$	—	$	—
Total assets at fair value	$	54.0	$	54.0	$	—	$	—