General - Basis of Presentation - Stock Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 04, 2021	Mar. 31, 2020
Stock Benefit Plans
Stock-based compensation	$ 6,637	$ 4,280
Payment of cash dividends	$ 201	21,367
Performance awards
Stock Benefit Plans
Aggregate payout if targets achieved (in shares)	186,000
Unrecognized compensation cost	$ 9,300
Stock-based compensation	0
Dividend Equivalent Rights
Stock Benefit Plans
Payment of cash dividends	200
Long Term Incentive Plan
Stock Benefit Plans
Stock-based compensation	6,562	4,205
Employee Stock Purchase Plan
Stock Benefit Plans
Stock-based compensation	$ 75	$ 75

Number of shares of aggregate payout if targets are achieved.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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