Required holding period for shares earned under perfomance based compensation.

No definition available.

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- Definition

This element represents the number of restricted stock units that are outstanding under the non-employee director plan.

+ References

No definition available.

+ Details

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- Definition

Number of trading days required for the share price to remain above the target price to meet vesting requirements.

+ References

No definition available.

+ Details

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- Definition

Target share price that must be met or exeeded for market-based stock options to vest

+ References

No definition available.

+ Details

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- Definition

Percentage of share-based compensation option award that vests over a defined period.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Vesting period for 100% vesting of amount.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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Period Type:	duration

- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

+ References

+ Details

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Balance Type:	debit
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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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+ Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

+ References

No definition available.

+ Details

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

+ Details

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Stock-Based Compensation (Details 4) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Compensation for Chief Executive Officer	May 02, 2013 Compensation for Chief Executive Officer	Jun. 30, 2013 Tranche one [Member] Compensation for Chief Executive Officer	Jun. 30, 2013 Tranche two [Member] Compensation for Chief Executive Officer	Jun. 30, 2013 Tranche three [Member] Compensation for Chief Executive Officer	Jun. 30, 2013 Tranche four [Member] Compensation for Chief Executive Officer
Stock based compensation disclosure
Compensation expense relating to the stock purchase plan and deferred compensation payable in stock	$ 145,000	$ 144,000
Restricted stock units outstanding (in shares)	91	74
Options awarded to Chief Executive Officer				500
Weighted-average exercise price of options awarded to Chief Executive Officer				$ 31.46
Grant date fair value				5,525,000
Vesting Percentage					25.00%	25.00%	25.00%	25.00%
Target Share Price, Option Vesting Requirement						$ 36.46	$ 41.46	$ 46.46
Vesting period					2 years 0 days	2 years 0 days
Share Price Target, Consecutive Trading Day Requirement						0 years 0 months 20 days	0 years 0 months 20 days	0 years 0 months 20 days
Required holding period for shares			2 years 0 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 11.05
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price			$ 31.46
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			1.48%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.86%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			44.05%