Customer Contracts

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

Customer Contracts

Customer Contracts

The following table presents the balances related to customer contracts as of December 31, 2019 and 2020:

(In millions)	Consolidated Balance Sheets Account	December 31, 2019		December 31, 2020
Accounts receivable, net	Accounts receivable, net (1)	$	350.3	$	483.0
Current portion of contract assets	Other current assets	7.8		12.2
Non-current portion of contract assets	Other non-current assets	7.2		13.9
Current portion of deferred revenue	Deferred revenue	66.6		76.7
Non-current portion of deferred revenue	Other non-current liabilities	14.2		14.2

(1)    Allowance for doubtful accounts and accrued customer credits was $17.0 million and $28.3 million as of December 31, 2019 and 2020, respectively.

The following table sets forth the changes in the allowance for doubtful accounts during the years ended December 31, 2018, 2019 and 2020:

(In millions)	Beginning Balance		Additions (1)		Write-offs of Accounts Receivables, Net of Recoveries		Ending Balance
For the years ending December 31,
2018	$	5.6	$	12.7	$	(10.8)	$	7.5
2019	7.5		13.3		(11.3)		9.5
2020	9.5		20.1		(13.4)		16.2

(1)    Additions to the allowance for doubtful accounts are charged to bad debt within selling, general and administrative expense.

Amounts recognized in revenue for the years ended December 31, 2018, 2019 and 2020, which were included in deferred revenue as of the beginning of each period totaled $35.1 million, $47.6 million and $59.5 million, respectively.

Cost Incurred to Obtain and Fulfill a Contract

As of December 31, 2019 and 2020, the balances of capitalized costs to obtain a contract were $55.1 million and $59.3 million, respectively, and the balances of capitalized costs to fulfill a contract were $21.7 million and $25.0 million, respectively. These capitalized costs are included in "Other non-current assets" on the Consolidated Balance Sheets.

Amortization of capitalized sales commissions and implementation costs for the years ended December 31, 2018, 2019 and 2020 was as follows:

	Year Ended December 31,
(In millions)	2018		2019		2020
Amortization of capitalized sales commissions	$	27.2	$	40.9	$	44.2
Amortization of capitalized implementation costs	9.5		14.8		17.4

Remaining Performance Obligations

As of December 31, 2020, the aggregate amount of transaction price allocated to remaining performance obligations was $922.9 million, of which 60% is expected to be recognized as revenue during 2021 and the remainder thereafter. These remaining performance obligations primarily relate to our fixed-term arrangements. Our other revenue arrangements are usage-based, and as such, we recognize revenue based on the right to invoice for the services performed.