As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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- Definition

Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

+ Details

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

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- Definition

The number of shares newly issued during the reporting period under the plan.

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- Definition

The total reduction to unamortized compensation cost for restricted shares forfeited during the period.

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The total fair value (on the date of issue) for restricted share awards issued during the period.

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Represents the number of installments in which the shares vest.

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Employee Share-Based Incentive Compensation Plans (Details 3) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended					9 Months Ended			3 Months Ended
	Mar. 31, 2007 Chairman and CEO WTM Restricted Stock	Sep. 30, 2011 WTM Restricted Stock	Jun. 30, 2011 WTM Restricted Stock	Mar. 31, 2011 WTM Restricted Stock	Sep. 30, 2010 WTM Restricted Stock	Sep. 30, 2011 WTM Restricted Stock	Sep. 30, 2010 WTM Restricted Stock	Dec. 31, 2010 WTM Restricted Stock installment	Mar. 31, 2010 Restricted shares that will vest in December, 2012
Activity in plan
Beginning of period (in shares)		73,500		46,250	98,750	46,250	91,900
Issued (in shares)	15,000					27,250	19,750		19,750
Vested (in shares)			(250)	(27,000)			(12,650)
Cancellations and change in assumed forfeitures (in shares)							(250)
Ending of period (in shares)		73,500	73,500		98,750	73,500	98,750
Unamortized grant date fair value
Unamortized grant date fair value, beginning balance		$ 18.9		$ 14.1	$ 20.9	$ 14.1	$ 23.7
Issued						9.9	6.7
Forfeited							(0.1)
Modified							(3.3)
Expense recognized		(2.8)			(3.3)	(7.9)	(9.4)
Unamortized grant date fair value, ending balance		$ 16.1	$ 18.9		$ 17.6	$ 16.1	$ 17.6
Number of installments in which the shares vest								3
Issued (in shares)	15,000					27,250	19,750		19,750