SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS - Allowance for Doubtful Accounts (Details) - Allowance for Doubtful Accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves
Balance at Beginning of Period	$ 34,889	$ 32,396	$ 47,745
Charges to Costs, Expenses and other	27,390	30,579	14,167
Write-off of Accounts Receivable	27,898	26,310	27,014
Other	(499)	(1,776)	(2,502)
Balance at End of Period	$ 33,882	$ 34,889	$ 32,396