Leases (Schedule of Lease Balance Classifications Within Consolidated Balance Sheets and Lease Activities) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Operating lease right-of-use assets
Balance as of December 29, 2018	$ 0
Right-of-use assets recorded from adoption of ASC 842	29,893
Right-of-use assets obtained in exchange for new lease obligations during the period	219	$ 0
Amortization of right-of-use asset during the period	(1,487)
Impairment of right-of-use asset on Portland, Oregon office (recorded in Restructuring charges)	(757)	0
Balance as of March 30, 2019	27,868
Operating lease liabilities
Balance as of December 29, 2018	0
Lease liabilities recorded from adoption of ASC 842	32,273
Lease liabilities incurred for new lease obligations during the period	219
Accretion of lease liabilities	508
Operating cash used by payments on lease liabilities	(2,597)	$ 0
Balance as of March 30, 2019	30,403
Current portion of operating lease liabilities	5,027
Long-term operating lease liabilities, net of current portion	$ 25,376