SEC Schedule II Valuation and Qualifying Accounts (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]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 32,069	$ 40,839	$ 46,531
Additions Charged Against Operations	3,614	11,417	9,697
Uncollectable Accounts Written-Off	(9,624)	(20,187)	(15,389)
Balance at End of Year	$ 26,059	$ 32,069	$ 40,839