SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS

12 Months Ended

Dec. 31, 2018

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):

	2018			2017			2016
Balance, beginning of year	$	42,409		$	39,543		$	43,455
Provision	15,634			13,489			5,136
Write-offs	(16,912		)	(10,623		)	(9,048		)
Balance, end of year	$	41,131		$	42,409		$	39,543

(b)     Index to Exhibits-See Exhibit Index for a description of the documents that are filed as Exhibits to this report on Form 10-K or incorporated by reference herein. 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.