Accounting Policies - Financial Data for Investments in Affiliated Companies (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accounting Policies [Abstract]
Revenue				$ 9,088
Gross profit				3,489
Net income				2,413
Equity in earnings of affiliated companies	$ 0	$ 0	$ 0	$ 677