Other Income, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Income and Expenses [Abstract]
Interest income	$ 162	$ 162	$ 451	$ 537
Other nonoperating income	511	607	1,594	1,904
Insurance policy (expense) income	(129)	453	(205)	233
Other nonoperating expense	0	0	(3)	0
Other income, net	$ 544	$ 1,222	$ 1,837	$ 2,674