SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for deferred tax asset
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 0	$ 0	$ 0
Charged to Expenses	0	0	0
Adjustments to Valuation Accounts	859	0	0
Deductions	0	0	0
Balance at End of Year	859	0	0
Allowance for uncollectible accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	7,451	5,952	6,242
Charged to Expenses	0	1,499	0
Adjustments to Valuation Accounts	0	0	0
Deductions	(1,731)	0	(290)
Balance at End of Year	5,720	7,451	5,952
Allowance for notes receivable
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	0	0	3,681
Charged to Expenses	0	0	0
Adjustments to Valuation Accounts	0	0	0
Deductions	0	0	(3,681)
Balance at End of Year	$ 0	$ 0	$ 0