Restricted Cash (Schedule Of Restricted Cash) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash	$ 47,372	$ 58,453
Restricted Cash - Current Asset [Member] | Securitization Escrow Accounts [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash	41,038	52,117
Restricted Cash - Current Asset [Member] | Payment and Performance Bonds [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash	400	402
Other Assets - Noncurrent [Member] | Surety Bonds and Workers Compensation [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash	$ 5,934	$ 5,934