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]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 27,854	$ 22,128	$ 24,868
Additions	13,411	13,597	10,928
Deductions	16,393	7,871	13,668
Balance at end of year	$ 24,872	$ 27,854	$ 22,128