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Debt - Additional Information (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Mar. 09, 2017 USD ($) $ / shares | Dec. 30, 2017 USD ($) | Dec. 30, 2017 KRW (₩)
Debt Instrument [Line Items] |  |  |
Cash dividend (in dollars per share) | $ / shares | $ 3 |  |
Cash dividend, subordinated debentures (in dollars per share) | $ / shares | $ 5 |  |
Decrease in stockholders' equity | $ 458,700,000 |  |
Increase in long term debt | 284,500,000 |  |
Decrease in cash | $ 174,200,000 |  |
Subordinated Debt [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt, stated interest rate |  | 6.00% | 6.00%
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 |  | 8,400,000 |
Jungwoo-Mueller [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Line of credit facility maximum borrowing capacity |  | $ 27,500,000 | ₩ 29,900,000,000.0
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 |  | 1.50% |
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 |  | 0.50% |
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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- Definition Amount of paid and unpaid paid-in-kind dividends (PIK) in debentures. + References No definition available. + Details
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- Definition The increase (decrease) in long term debt during the period. + References No definition available. + Details
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- Definition Amount of increase (decrease) in cash. Cash is the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Includes effect from exchange rate changes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 230 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49171198&loc=d3e33268-110906 + Details
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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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