Employee Retirement Plans (Schedule of Contributions Made by the Company to Each Multiemployer Plan) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 333	$ 329	$ 328
National Integrated Group Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions	246	233	222
Sheet Metal Workers National Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions	56	61	78
Sheet Metal Workers Pension Plan Of Northern California [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 31	$ 35	$ 28