Acquisition Activity (Schedule of Acquisition Costs) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 31, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Acquisition costs	$ 443	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 443	$ 0	$ 0
Dynamic Systems Inc.
Business Acquisition [Line Items]
Acquisition costs									443
Accounting and legal fees | Dynamic Systems Inc.
Business Acquisition [Line Items]
Acquisition costs									214
Appraisal fees | Dynamic Systems Inc.
Business Acquisition [Line Items]
Acquisition costs									13
Other | Dynamic Systems Inc.
Business Acquisition [Line Items]
Acquisition costs									$ 216