XML 71 R55.htm IDEA: XBRL DOCUMENT v3.10.0.1
Restricted Cash (Schedule of Cash, Cash Equivalents and Restricted Cash) (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Restricted Cash And Cash Equivalents Items [Line Items]        
Cash and cash equivalents $ 143,444 $ 68,783 $ 146,109  
Restricted cash - current asset 32,464 32,924    
Total cash, cash equivalents, and restricted cash 178,300 104,295 185,970 $ 146,619
Securitization Escrow Accounts [Member] | Restricted Cash - Current Asset [Member]        
Restricted Cash And Cash Equivalents Items [Line Items]        
Restricted cash - current asset 32,261 32,699 36,607  
Payment and Performance Bonds [Member] | Restricted Cash - Current Asset [Member]        
Restricted Cash And Cash Equivalents Items [Line Items]        
Cash and cash equivalents 203 225 179  
Surety Bonds and Workers Compensation [Member] | Other Assets - Noncurrent [Member]        
Restricted Cash And Cash Equivalents Items [Line Items]        
Restricted cash - noncurrent asset $ 2,392 $ 2,588 $ 3,075