Segment and Related Information, Reconciliation of Segment Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Identifiable assets by business segment [Abstract]
Identifiable assets	$ 124,049	$ 115,874
United States [Member] | Reportable Geographical Components [Member]
Identifiable assets by business segment [Abstract]
Identifiable assets	110,369	100,583
Other Countries [Member] | Reportable Geographical Components [Member]
Identifiable assets by business segment [Abstract]
Identifiable assets	$ 13,680	$ 15,291