Schedule II - Valuation and Qualifying Accounts (Details) - Allowance for Doubtful Accounts [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance at Beginning of Period	$ 15,347	$ 16,248	$ 16,646
Valuation Allowances and Reserves, Additions	2,640	790	1,384
Valuation Allowances and Reserves, Deductions	1,809	1,691	1,782
Valuation Allowances and Reserves, Balance at End of Period	$ 16,178	$ 15,347	$ 16,248