XML 52 R31.htm IDEA: XBRL DOCUMENT v3.8.0.1
Schedule II - Consolidated Valuation and Qualifying Accounts
 12 Months Ended
Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]  
Schedule II - Consolidated Valuation and Qualifying Accounts
SCHEDULE II - CONSOLIDATED VALUATION AND QUALIFYING ACCOUNTS

(in thousands)
 
Additions
 
 
Allowance for doubtful accounts receivable - Year ended December 31,

Balance at beginning of period
Charged to costs and expenses
Transferred from (to) allowance for accounts / notes receivable
(1)
Deductions
Balance at end of period
2017
$
7,706

$
3,000

$
—

$
(1,550
)
$
9,156

2016
6,938

1,191

—

(423
)
7,706

2015
4,644

3,302

—

(1,008
)
6,938

(1) Uncollectible accounts written off, net of recoveries and adjustments to estimates for the allowance accounts.