SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction

We expect to recognize as revenue the following amounts related to our remaining performance obligations as of December 31, 2020, inclusive of the foreign exchange impact:

Performance Obligation	Balance
	(In millions)
Less than 1 year	$	33.9
1 to 3 years	31.6
3 to 5 years	21.2
Thereafter	43.9
Total remaining performance obligation	$	130.6

Reconciliation of Weighted-Average Outstanding Shares Used in Calculations of Basic and Diluted EPS

A reconciliation of the weighted-average outstanding shares used in the two calculations is as follows:

	Twelve Months Ended December 31,
	2020	2019	2018
	(In millions)
Weighted-average shares outstanding (basic)	121.5	120.9	120.4
Effect of dilutive securities:
Stock options and restricted stock units	1.3	1.1	1.0
Weighted-average shares outstanding (diluted)	122.8	122.0	121.4

Accounts Receivable, Allowance for Credit Loss

Below is a rollforward of our allowance for doubtful accounts for the twelve months ended December 31, 2020 and 2019:

	Twelve Months Ended December 30,
	2020	2019
	(In millions)
Allowance for doubtful accounts, beginning of period	$11.2	$10.9
Current period bad debt expense	6.3	5.4
Write-offs, net of recoveries	(4.6)	(5.1)
Allowance for doubtful accounts, end of period	$12.9	$11.2

Useful Life of Other Purchased Intangible Assets

All of our other purchased intangible assets are also amortized on a straight-line basis. 

Asset	Useful Life
	(In years)
Purchased data files	15
Acquired software and technology	1 to 10
Non-compete agreements	5
Proprietary database	6 to 13
Customer relationships	7 to 25
Trade names	2 to 15

Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table presents assets and liabilities measured at fair value on a recurring basis:

			Fair Value Measurements at Reporting Date Using:
Description	Fair Value at December 31, 2020		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(In millions)
Assets and Liabilities:
Deferred Compensation Plan Assets (1)	$	42.3	$	42.3	$	—	$	—
Deferred Compensation Plan Liability (1)	(42.3)		—		(42.3)		—
Total assets and liabilities	$	—	$	42.3	$	(42.3)	$	—

(1)    We maintain deferred compensation plans that allow for certain management employees to defer the receipt of compensation (such as salary and incentive compensation) until a later date based on the terms of the plans. The liability representing benefits accrued for plan participants is valued at the quoted market prices of the participants’ investment elections. The asset consists of mutual funds reflective of the participants investment selections and is valued at daily quoted market prices.