Schedule II - Valuation And Qualifying Accounts and Reserves (Details) (Allowance For Doubtful Accounts [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance For Doubtful Accounts [Member]
Allowance for Doubtful Accounts Receivable [Roll Forward]
Beginning Balance	$ 3,919		$ 3,970		$ 4,506
Additions Charged to Costs and Expenses	4,470		1,990		2,160
Additions Charged to Other Accounts	0		0		0
Deductions	2,253	[1]	2,041	[1]	2,696	[1]
Ending Balance	$ 6,136		$ 3,919		$ 3,970

[1] Represents write-offs