Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2017

Assets and Liabilities Measured at Fair Value on Recurring Basis

The following tables summarize the basis used to measure financial assets and liabilities that are carried at fair value on a recurring basis in the consolidated balance sheets.

			Basis of fair value measurement
	As of December 31, 2017		Significant other observable inputs (Level 2)
Assets
Foreign currency contracts	$	2.2	$	2.2

			Basis of fair value measurement
	As of December 31, 2016		Significant other observable inputs (Level 2)
Assets
Foreign currency contracts	$	1.7	$	1.7
Available-for-sale securities	328.7		328.7
Total assets	$	330.4	$	330.4
Liabilities
Foreign currency contracts	1.5		1.5
Total liabilities	$	1.5	$	1.5

Assets Measured at Fair Value on a Nonrecurring Basis

The fair value as of the measurement date, net book value as of the end of the year and related impairment charge for assets measured at fair value on a nonrecurring basis subsequent to initial recognition during the years ended December 31, 2017, 2016 and 2015 were as follows:

	Year Ended December 31, 2017				As of December 31, 2017
	Impairment Charge		Fair Value Measurement (Level 3)		Net Book Value
Long-lived assets held for sale or disposal	$	1.3	$	0.7	$	—
Goodwill		21.3		—		—
Other intangible assets		0.2		—		—
Total	$	22.8	$	0.7	$	—

	Year Ended December 31, 2016				As of December 31, 2016
	Impairment Charge		Fair Value Measurement (Level 3)		Net Book Value
Long-lived assets held for sale or disposal	$	0.6	$	—	$	—
Goodwill		527.8		15.2		15.2
Other intangible assets		29.7		4.6		4.3
Total	$	558.1	$	19.8	$	19.5

	Year Ended December 31, 2015				As of December 31, 2015
	Impairment Charge		Fair Value Measurement (Level 3)		Net Book Value
Long-lived assets held and used	$	0.3	$	—	$	—
Long-lived assets held for sale or disposal		1.5		2.8		—
Goodwill		18.0		—		—
Other intangible assets		11.9		—		—
Total	$	31.7	$	2.8	$	—

Fair Values, Valuation Techniques and Related Unobservable Inputs of Level Three

The following table presents the fair value, valuation techniques and related unobservable inputs for these Level 3 measurements for the years ended December 31, 2016 and 2015:

	Fair Value		Valuation Technique	Unobservable Input	Range
2016
Client relationships	$	4.6	Excess earnings	Attrition rate	5.0%
				Discount rate	13.0%
2015
Client relationships	$	—	Excess Earnings	Discount rate	2.7%