Investments (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2015 USD ($)
Notes Receivable Current [Member]
Balance at beginning of period	$ 150
Total gains or (losses) (realized or unrealized)
Purchases
Sales
Transfers
Balance at end of period	$ 150
Investments [Member]
Balance at beginning of period	$ 3,880
Total gains or (losses) (realized or unrealized)
Purchases
Sales
Transfers
Balance at end of period	$ 3,880