Maximum excess availability level at which financial maintenance covenants would apply.

No definition available.

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Maximum excess availability level at which financial maintenance covenants would apply, as a percentage of aggregate commitments.

+ References

No definition available.

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- Definition

Total other amounts reducing excess availability.

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No definition available.

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Potential increase in the size of credit facility.

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No definition available.

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Represents the write-off of unamortized discount in an extinguishment of debt.

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No definition available.

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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. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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

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No definition available.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

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-Name Regulation S-X (SX)

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-Subparagraph (SX 210.5-02.22(a)(2))

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Amount of the required periodic payments applied to principal.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

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No definition available.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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No definition available.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Date the credit facility terminates, in CCYY-MM-DD format.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Borrowing Arrangements (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Apr. 07, 2015	Sep. 30, 2014	Sep. 30, 2013
Borrowing rate in addition to LIBOR			32500.00%
Cash and cash equivalents	$ 34.1	$ 105.1	$ 34.1	$ 105.1		$ 161.1	$ 123.6
Loss on early extinguishment of debt	0	0	31.3	0
Gain (Loss) on Repurchase of Debt Instrument			(25.2)
Write off of Deferred Debt Issuance Cost			4.4
Write off of Unamortized Discount			1.7mwa_WriteoffofUnamortizedDiscount
Payments of Debt Issuance Costs			8.4us-gaap_PaymentsOfDebtIssuanceCosts	0us-gaap_PaymentsOfDebtIssuanceCosts
Debt Instrument, Unamortized Discount	2.4		2.4
Domestic Line of Credit [Member]
Revolving credit facility amount	(225)		(225)
Potential increase size of the credit facility by an additional amount			150
Line of Credit Facility, Interest Rate at Period End	17500.00%		17500.00%
Agreement termination date			Dec. 18, 2017
Aggregate commitments availability			22.5
Aggregate commitments availability, percentage			10.00%
Outstanding letter of credit accrued fees and expenses	42.4		42.4
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses	172.8		172.8
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			3750.00%
Swing Line Loans [Member]
Revolving credit facility amount	(25)		(25)
Letters Of Credit Outstanding [Member]
Revolving credit facility amount	(60)		(60)
Secured Debt [Member]
Long-term Debt, Gross	500.0		500.0
Debt Instrument, Periodic Payment, Principal			1.25
Agreement termination date			Nov. 25, 2021
Financial Liabilities Fair Value Disclosure	$ 501.2		$ 501.2
Minimum [Member] \| Domestic Line of Credit [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			2500.00%
Maximum [Member] \| Domestic Line of Credit [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			3750.00%
London Interbank Offered Rate (LIBOR) [Member] \| Secured Debt [Member]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum			0.75%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Long-term Debt [Member]
Borrowing rate in addition to LIBOR	7500.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Domestic Line of Credit [Member]
Borrowing rate in addition to LIBOR			17500.00%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Domestic Line of Credit [Member]
Borrowing rate in addition to LIBOR			22500.00%
Base Rate [Member] \| Maximum [Member] \| Domestic Line of Credit [Member]
Borrowing rate in addition to LIBOR			12500.00%
Subsequent Event [Member]
Derivative, Inception Date					Apr. 07, 2015