Stock Based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Assumptions used to estimate fair value of options granted [Abstract]
Expected stock price volatility, minimum (in hundredths)			53.52%	48.80%
Expected stock price volatility, maximum (in hundredths)			57.19%	53.21%
Risk-free interest rate, minimum (in hundredths)			1.24%	1.33%
Risk-free interest rate, maximum (in hundredths)			1.33%	2.84%
Stock Options and Restricted Stock granted [Abstract]
Number of options and shares of restricted stock granted (in shares)	28	9	276	204
Fair value of options and restricted stock granted	$ 197	$ 84	$ 2,349	$ 2,505
Unrecognized compensation cost related to nonvested options and restricted shares outstanding	2,631	2,981	2,631	2,981
Weighted average period over which cost is expected to be recognized			2 years
Stock based compensation expense	$ 424	$ 508	$ 2,665	$ 1,578
Maximum [Member]
Assumptions used to estimate fair value of options granted [Abstract]
Expected dividend yield (in hundredths)			2.73%	2.66%
Weighted-average expected life of options			7 years 8 months 12 days	7 years 7 months 17 days
Forfeiture rate (in hundredths)			3.00%	3.00%
Minimum [Member]
Assumptions used to estimate fair value of options granted [Abstract]
Expected dividend yield (in hundredths)				1.57%
Weighted-average expected life of options			6 years 2 months 16 days	6 years 3 months 11 days
Forfeiture rate (in hundredths)			1.00%	1.00%

Number of share options (or share units) and shares of restricted stock granted during the period.

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- Definition

The total fair value of equity-based awards and restricted stock for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

No definition available.

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- Definition

The estimated measure of the percentage by which a share under options is expected to cancelled during a reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

No definition available.

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 28

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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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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 2

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

The estimated measure of the maximum 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

No definition available.

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The estimated measure of the minimum 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

No definition available.

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- Definition

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

+ References

No definition available.

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

+ References

No definition available.

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