Stock-Based Compensation (Fair Value Assumptions) (Details) (USD $) In Thousands, except Share data in Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2011
ESPP maximum employee subscription rate	10.00%
Share-based compensation arrangement, discount from market price, lesser at offering period or purchase date	85.00%
ESPP maximum annual share replenishment			2.0
ESPP share replenishment In period			2.0
Number of ESPP shares available for future issuance	3.5
ESPP offering period, in months	6
Share-based Compensation Arrangement, Fair Value Assumptions and Methodology [Abstract]
Expected stock price volatility	33.00%	41.00%
Risk-free interest rate	0.10%	0.20%
Dividend yield	3.40%	3.70%
Expected life of options (in years)	0.50	0.50
Employee Stock Purchase Plan Additional Information [Abstract]
Tax benefits realized in connection with the disqualifying dispositions of shares purchased under the ESPP	$ 475	$ 356
Weighted average fair value per share based on Black-Scholes model	$ 9.16	$ 6.53

Employee Stock Purchase Plan Additional Information [Abstract]

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Espp Maximum Annual Share Replenishment

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Espp Share Replenishment In Period

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Number Of Espp Shares Available For Future Issuance

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Stock Based Compensation Offering Period In Months

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Tax Benefits Realized From Espp

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Weighted Average Fair Value Per Share

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- Definition

The discount rate from market value on offering date that participants pay for shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph e(2)(c)

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- Definition

The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior.

+ 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 D

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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

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

-Publisher FASB

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-Subparagraph e(2)(b)

-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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- Definition

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

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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