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v3.20.4

Debt - Narrative (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Mar. 09, 2017 $ / shares | Dec. 26, 2020 USD ($) | Dec. 28, 2019 USD ($) | Dec. 29, 2018 USD ($) | Dec. 26, 2020 KRW (₩)
Debt Instrument [Line Items] |  |  |  |  |
Cash dividend (in dollars per share) | $ / shares | $ 3.00 |  |  |  |
Cash dividend, subordinated debentures (in dollars per share) | $ / shares | $ 5.00 |  |  |  |
Interest paid |  | $ 19,800,000 | $ 25,400,000 | $ 25,200,000 |
Subordinated Debt [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt, stated interest rate (as a percent) |  | 6.00% |  |  | 6.00%
Debt instrument, call feature, period, latest |  | 5 years |  |  |
Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit facility, current borrowing capacity |  | $ 350,000,000.0 |  |  |
Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Outstanding letters of credit |  | 19,400,000 |  |  |
Jungwoo-Mueller [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit facility maximum borrowing capacity |  | $ 23,500,000 |  |  | ₩ 25,800,000,000
Minimum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility commitment fee |  | 0.15% |  |  |
Maximum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility commitment fee |  | 0.30% |  |  |
LIBOR [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 1.375% |  |  |
LIBOR [Member] | Minimum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 1.125% |  |  |
LIBOR [Member] | Maximum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 1.625% |  |  |
Base Rate [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 0.375% |  |  |
Base Rate [Member] | Minimum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 0.125% |  |  |
Base Rate [Member] | Maximum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 0.625% |  |  |

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