Schedule II - Valuation and Qualifiying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, Beginning of Year	$ 848	$ 1,617	$ 1,630
Additions Charged to Revenues, Costs and Expenses	559	885	997
Additions/(Deductions) Charged to Balance Sheet Accounts	741	(1,230)	(109)
(Deductions) Charged to Revenues, Costs and Expenses	(244)	(424)	(901)
Balance, End of Year	1,904	848	1,617
Valuation Allowance of Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, Beginning of Year	76,340	81,981	77,647
Additions Charged to Revenues, Costs and Expenses	0	0	4,334
Additions/(Deductions) Charged to Balance Sheet Accounts	0	0	0
(Deductions) Charged to Revenues, Costs and Expenses	(5,866)	(5,641)	0
Balance, End of Year	$ 70,474	$ 76,340	$ 81,981