SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS

12 Months Ended

Dec. 31, 2019

SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]

SCHEDULE II. VALUTAION AND QUALIFYING ACCOUNTS

SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS

Allowance for Doubtful Accounts

The transactions in the allowance for doubtful accounts for the years ended December 31, were as follows (in thousands): 

	2019		2018		2017
Balance, beginning of year	$	41,131	$	42,409	$	39,543
Provision	5,853		15,634		13,489
Write-offs	(14,146)		(16,912)		(10,623)
Balance, end of year	$	32,838	$	41,131	$	42,409

(b)  Index to Exhibits-Any document incorporated by reference is identified by a parenthetical referencing the SEC filing which included the document. We will furnish a copy of any Exhibit at no cost to a security holder upon request.