Schedule II Valuation and Qualifying Accounts (Details) (Allowance for Doubtful Accounts [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Allowance for Doubtful Accounts [Member]
Allowance for doubtful accounts:
Balance, beginning of period	$ 10,818		$ 12,407		$ 15,284
Charged to Costs and Expenses	5,725		7,064		3,977
Other	1,395	[1]	1,754	[1]	2,112	[1]
Deductions	7,853	[2]	10,407	[2]	8,966	[2]
Balance, end of period	$ 10,085		$ 10,818		$ 12,407

[1] Recoveries.

[2] Uncollectible accounts written off.