Schedule II: Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 1,020	$ 102,217	$ 110,610
Charged (credited) to expense	(337)	(100,792)	(8,035)
Deductions from reserves	(415)	(405)	(358)
Balance at end of period	268	1,020	102,217
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	332	737	1,043
Charged (credited) to expense	113	0	52
Deductions from reserves	(177)	(405)	(358)
Balance at end of period	268	332	737
Allowance for Notes Receivable [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	688	988	1,501
Charged (credited) to expense	(450)	(300)	(513)
Deductions from reserves	(238)	0	0
Balance at end of period	0	688	988
Valuation Allowance on Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period		100,492	108,066
Charged (credited) to expense		(100,492)	(7,574)
Deductions from reserves		0	0
Balance at end of period		$ 0	$ 100,492