Annual report pursuant to Section 13 and 15(d)

Schedule II - Valuation and Qualifying Accounts (Details)

v3.3.1.900
Schedule II - Valuation and Qualifying Accounts (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Valuation and Qualifying Accounts Disclosure [Line Items]        
Valuation Allowances and Reserves, Balance $ 2,689 $ 2,836 $ 2,153 $ 1,763
Valuation Allowances and Reserves, Charged to Cost and Expense 4,837 2,745 2,869  
Valuation Allowances and Reserves, Deductions 4,984 2,062 2,479  
Allowance for Doubtful Accounts [Member]        
Valuation and Qualifying Accounts Disclosure [Line Items]        
Valuation Allowances and Reserves, Balance 1,310 2,155 1,583 1,149
Valuation Allowances and Reserves, Charged to Cost and Expense 33 241 423  
Valuation Allowances and Reserves, Deductions [1] 878 (331) (11)  
Allowance for revenue adjustments [Member]        
Valuation and Qualifying Accounts Disclosure [Line Items]        
Valuation Allowances and Reserves, Balance [2] 1,095 408 336 295
Valuation Allowances and Reserves, Charged to Cost and Expense [2] 4,793 2,465 2,531  
Valuation Allowances and Reserves, Deductions [2],[3] 4,106 2,393 2,490  
Valuation Allowance of Deferred Tax Assets [Member]        
Valuation and Qualifying Accounts Disclosure [Line Items]        
Valuation Allowances and Reserves, Balance 284 273 234 $ 319
Valuation Allowances and Reserves, Charged to Cost and Expense $ 11 $ 39 $ (85)  
[1] Represents uncollectible accounts written off, net of recoveries
[2] Represents an allowance for adjustments to accounts receivable due to disputed rates, accessorial charges and other aspects of previously billed shipments.
[3] Represents adjustments to billed accounts receivable