The weighted average effective interest rate, excluding the impact of the interest rate swap.

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- Definition

Remaining required principal payments on long-term debt for the current fiscal year.

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The percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). 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.

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The average effective interest rate during the reporting period.

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-Name Regulation S-X (SX)

-Number 210

-Section 02

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of the required periodic payments applied to principal.

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- Definition

Amount of long-term debt maturing in year three following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Amount of long-term debt maturing in year two following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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Including the current and noncurrent portions, the carrying value as of the balance sheet date of notes payable to banks, excluding mortgage notes, initially due beyond one year or beyond the operating cycle if longer.

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Long-Term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Jul. 31, 2008	Dec. 31, 2011 July 31, 2008 Term Loan [Member]	Jul. 31, 2008 July 31, 2008 Term Loan [Member] Prime Rate [Member]	Sep. 30, 2011 July 31, 2008 Term Loan [Member] London Interbank Offered Rate, L.I.B.O.R. [Member]	Jan. 31, 2009 July 31, 2008 Term Loan [Member] London Interbank Offered Rate, L.I.B.O.R. [Member]	Jul. 31, 2008 July 31, 2008 Term Loan [Member] London Interbank Offered Rate, L.I.B.O.R. [Member]
Debt Instrument [Line Items]
Borrowed from syndicate of banks					$ 355.0
Fixed portion of the variable rate							0.50%	0.75%	0.75%	1.50%
Quarterly principal payments			21.3
Principal payment for 2011	10.6		10.6
Principal payment for 2012	74.4		74.4
Principal payment for 2013	53.1		53.1
Weighted average interest rate on term loan	1.00%	1.28%	1.04%	1.66%
Weighted average effective interest rate, excluding the impact of the interest rate swap				1.10%
Variable interest rate						1.12%
Term loan payable in quarterly installments with a final maturity of July 31, 2013						$ 138.2