Schedule II - Valuation and Qualifying Accounts (Details) - Valuation and Qualifying Accounts (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts [Member]
Valuation Allowance [Line Items]
Balance at beginning of period	$ 16,402	$ 18,059	$ 15,712
Charged to expenses	3,521	6,309	7,027
Deductions	(9,152)	(7,966)	(4,680)
Balance at end of period	10,771	16,402	18,059
Valuation Allowance of Deferred Tax Assets [Member]
Valuation Allowance [Line Items]
Balance at beginning of period	71,912	66,520	43,596
Adjustments to valuation accounts	(8,200)	5,392	22,924
Balance at end of period	$ 63,712	$ 71,912	$ 66,520