Debt (Details) (USD $)	6 Months Ended
Jun. 30, 2012	Jul. 02, 2011	Dec. 31, 2011
Debt Instrument [Line Items]
Debt	$ 33,515,000		$ 197,741,000
Less current portion of debt	(25,715,000)		(41,265,000)
Long-term debt	7,800,000		156,476,000
Principal amount of debt redeemed	148,676,000	250,000
6% Subordinated Debentures [Member]
Debt Instrument [Line Items]
Debt	0		148,176,000
Debt, stated interest rate (in hundredths)	6.00%
Debt instrument maturity date	Dec. 31, 2014
Principal amount of debt redeemed	148,200,000
Interest paid upon redemption of debentures	1,300,000
2001 Series IRB [Member]
Debt Instrument [Line Items]
Debt	8,750,000		9,250,000
Debt, stated interest rate (in hundredths)	1.39%
Debt instrument maturity date	Dec. 31, 2021
Mueller-Xingrong line of credit [Member]
Debt Instrument [Line Items]
Debt	24,715,000		40,265,000
Debt, stated interest rate (in hundredths)	6.00%
Debt instrument maturity date	Dec. 31, 2012
Other [Member]
Debt Instrument [Line Items]
Debt	$ 50,000		$ 50,000

Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 2, 4

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- Definition

The amount of cash paid for interest during the period.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 29

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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