Allowance for Credit Losses (Tables)

12 Months Ended

Dec. 31, 2020

Credit Loss [Abstract]

Accounts Receivable, Allowance for Credit Loss

The following table sets forth the Company's allowance for credit losses (in thousands):

	2020		2019		2018
Balance as of January 1	$	26,828	$	22,571	$	31,193
Impact from adoption of ASC 606(1)	—		—		(7,129)
Additions(2)	32,077		30,092		24,214
Deductions(3)	(25,537)		(25,835)		(25,707)
Balance as of December 31(4)	$	33,368	$	26,828	$	22,571

(1)Upon the adoption of ASC 606, the Company reclassified amounts related to accrued service credits to clients from the allowance for credit losses to Accrued liabilities on its consolidated balance sheet.

(2)For the years ended December 31, 2020, 2019 and 2018, represents provision for bad debt expense of $32.1 million, $30.1 million, and $24.2 million respectively, which is included in General and administrative expense.

(3)For the years ended December 31, 2020, 2019 and 2018, represents amounts written off as uncollectible, net of recoveries.

(4)As of December 31, 2020, $33.0 million of the allowance is attributable to Accounts receivable and $0.3 million is attributable to Contract assets.