Share Based Compensation (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011 Y	Sep. 30, 2010 Y	Sep. 30, 2011 Y D business segment market	Sep. 30, 2010 Y
Assumptions
Risk-free interest rate	1.97%	2.14%	1.97%	2.31%
Expected dividend yield	2.64%	0.63%	2.62%	0.67%
Expected volatility of Huntington's common stock	30.00%	32.50%	30.00%	38.60%
Expected option term (years)	6.0	6.0	6.0	6.0
Weighted-average grant date fair value per share	$ 1.40	$ 2.05	$ 1.41	$ 2.21

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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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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

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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

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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.

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