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Schedule II - Valuation and Qualifying Accounts
 12 Months Ended
Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]  
Schedule of Valuation and Qualifying Accounts Disclosure
Description
 
Balance  at
Beginning
of Year 
 
Costs and
Expenses
 
Deductions (1)
 
Balance at  
End  of Year
Allowance for doubtful accounts
 
 
 
 
 
 
 
 
Year Ended December 31, 2018
 
$
17,230

 
2,123

 
(3,992
)
 
$
15,361

Year Ended December 31, 2017
 
$
12,252

 
7,264

 
(2,286
)
 
$
17,230

Year Ended December 31, 2016
 
$
11,175

 
6,194

 
(5,117
)
 
$
12,252

_________________
(1)
Deductions primarily represent uncollectible balances of accounts receivable written off, net of recoveries.