Derivative Financial Instruments (Schedule of Offsetting of Derivative Assets) (Details) - USD ($) $ in Thousands	Sep. 27, 2020	Dec. 31, 2019
Offsetting of Derivative Assets [Line Items]
Gross Amounts of Recognized Assets	$ 110	$ 27
Gross Amounts Offset in the Unaudited Condensed Consolidated Balance Sheets	0	0
Net Amounts Of Assets Presented in the Unaudited Condensed Consolidated Balance Sheets	110	27
Financial Instruments	(5)	(27)
Cash Collateral Pledged	0	0
Net Amount	105	0
HSBC
Offsetting of Derivative Assets [Line Items]
Gross Amounts of Recognized Assets	29	6
Gross Amounts Offset in the Unaudited Condensed Consolidated Balance Sheets	0	0
Net Amounts Of Assets Presented in the Unaudited Condensed Consolidated Balance Sheets	29	6
Financial Instruments	(5)	(6)
Cash Collateral Pledged	0	0
Net Amount	24	0
Wells Fargo Bank
Offsetting of Derivative Assets [Line Items]
Gross Amounts of Recognized Assets	81	21
Gross Amounts Offset in the Unaudited Condensed Consolidated Balance Sheets	0	0
Net Amounts Of Assets Presented in the Unaudited Condensed Consolidated Balance Sheets	81	21
Financial Instruments	0	(21)
Cash Collateral Pledged	0	0
Net Amount	$ 81	$ 0

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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