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Debt - Narrative (Details)		12 Months Ended
Debt - Narrative (Details)	Mar. 09, 2017 $ / shares	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 29, 2018 KRW (₩)
Debt Instrument [Line Items]
Cash dividend (in dollars per share) \| $ / shares	$ 3
Cash dividend, subordinated debentures (in dollars per share) \| $ / shares	$ 5
Interest paid		$ 25,200,000	$ 13,800,000	$ 7,100,000
Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt, stated interest rate		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		8,500,000
Jungwoo-Mueller [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity		$ 25,300,000			₩ 28,800,000,000.0
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		1.625%
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		0.625%
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%