The weighted average fair value for equity-based awards other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The high end of the range of 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.

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The low end of the range of 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.

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Represents the estimated measure of the percentage of the number of shares (or other type of equity) under an equity-based award plan expected to be forfeited during the vesting period.

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The high end of the range of the estimated measure of the percentage by which a share price of a peer group 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, which is the same as the standard deviation of the differences in the natural logarithms of stock prices plus dividends, if any, over the period.

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The low end of the range of the estimated measure of the percentage by which a share price of a peer group 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, which is the same as the standard deviation of the differences in the natural logarithms of stock prices plus dividends, if any, over the period.

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Represents the high end of the range of the fair value percentage used for determining the fair value of the awards.

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Represents the low end of the range of the fair value percentage used for determining the fair value of the awards.

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- Definition

The market value of options during the reporting period as calculated by applying the disclosed option pricing methodology.

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The weighted average fair value of options during the reporting period.

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- Definition

Represents the term of the plan, expressed in years.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(1)
-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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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
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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 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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 1
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section D
-Subsection 2

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-SubTopic 10
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

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

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

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- Definition

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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Stock-Based Awards and Programs (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Stock-Based Awards and Programs
Compensation expense	$ 218	$ 730	$ 959	$ 1,528	$ 2,624	$ 2,572
Tax benefit recognized	$ 68	$ 261	$ 339	$ 549	$ 950	$ 915
Performance-Based Restricted Stock Awards
Assumptions used for estimating fair value of grants outstanding
Weighted average fair value of grants (in dollars per share)			$ 21.84	$ 18.36
Risk-free interest rate, low end of range (as a percent)			0.11%	0.22%
Risk-free interest rate, high end of range (as a percent)			0.60%	0.80%
Expected volatility (as a percent)			27.40%	28.60%
Expected volatility of peer group stock, low end of range (as a percent)			20.80%	22.40%
Expected volatility of peer group stock, high end of range (as a percent)			82.20%	83.00%
Dividend yield (as a percent)				7.00%
Dividend yield, low end of range (as a percent)			0.00%
Dividend yield, high end of range (as a percent)			4.20%
Expected forfeiture rates (as a percent)			3.00%	3.00%
Plan cycle (in years)			3	3
Fair value percentage, low end of range (as a percent)			67.00%	124.00%
Fair value percentage, high end of range (as a percent)			88.00%	152.00%
Weighted average fair value per share (in dollars per share)	$ 15.45	$ 26.21	$ 15.45	$ 26.21	$ 15.45	$ 26.21
Stock Options
Assumptions used for estimating fair value of grants outstanding
Risk-free interest rate, low end of range (as a percent)			0.25%	0.55%
Risk-free interest rate, high end of range (as a percent)			1.77%	2.23%
Expected volatility (as a percent)			24.00%	24.00%
Dividend yield (as a percent)				7.00%
Dividend yield, low end of range (as a percent)			3.20%
Dividend yield, high end of range (as a percent)			4.70%
Expected life (in months)			78	78
Market value (in dollars per share)			$ 19.26	$ 18.77
Weighted average fair value per option (in dollars per share)	$ 1.55	$ 1.05	$ 1.55	$ 1.05	$ 1.55	$ 1.05
Employee Stock Purchase Plan
Assumptions used for estimating fair value of grants outstanding
Weighted average fair value of grants (in dollars per share)			$ 3.17	$ 2.28
Risk-free interest rate (as a percent)			0.18%	0.35%
Expected volatility (as a percent)			22.00%	17.00%
Dividend yield (as a percent)			2.60%	7.20%
Expected life (in months)			12	12