Stock and Incentive Compensation Plans (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Compensation expense - Stock and Incentive plans [Abstract]
Compensation expense - Stock and Incentive plans	$ 1,022	$ 1,127
Performance Based Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ROATE Performance measure (in hundredths)	100.00%
TSR Performance measure (in hundredths)	100.00%
Stock and incentive plan [Roll Forward]
Outstanding/Nonvested shares or units, beginning of period (in shares)	159,583
Granted (in shares)	62,119
Granted - excess shares (in shares)	0
Exercised or released from restriction (in shares)	(54,784)
Expired (in shares)	0
Forfeited (in shares)	(202)
Outstanding/Nonvested shares or units, end of period (in shares)	166,716
Compensation expense - Stock and Incentive plans [Abstract]
Compensation expense - Stock and Incentive plans	211	219
Time Vested Award [Member]
Stock and incentive plan [Roll Forward]
Outstanding/Nonvested shares or units, beginning of period (in shares)	317,573
Granted (in shares)	86,955
Granted - excess shares (in shares)	10,809
Exercised or released from restriction (in shares)	(66,456)
Expired (in shares)	0
Forfeited (in shares)	(3,925)
Outstanding/Nonvested shares or units, end of period (in shares)	344,956
Compensation expense - Stock and Incentive plans [Abstract]
Compensation expense - Stock and Incentive plans	$ 811	$ 908
Restricted Stock [Member] \| Performance Based Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3Y
Restricted Stock [Member] \| Time Vested Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3Y
Stock option-based awards [Member]
Stock and incentive plan [Roll Forward]
Outstanding/Nonvested shares or units, beginning of period (in shares)	699,600
Granted (in shares)	0
Granted - excess shares (in shares)	0
Exercised or released from restriction (in shares)	(11,800)
Expired (in shares)	(14,500)
Forfeited (in shares)	0
Outstanding/Nonvested shares or units, end of period (in shares)	673,300
2005 Stock and Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting percentage per year (in hundredths)	20.00%
Stock and incentive compensation plan, contractual term	7 years
1997 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock and incentive compensation plan, contractual term	10 years
Vesting period (in years)	4Y

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Level of performance goal measured by return on average tangible equity (ROATE) for a share based compensation plan.

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- Definition

Gross number of excess share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The period between the balance sheet date and expiration for stock and incentive compensation awards under the plan, which may be expressed in a decimal value for number of years.

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No definition available.

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- Definition

Annual vesting percentage of stock options.

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No definition available.

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Level of performance goal measured by total shareholder return (TSR) for a share based compensation plan.

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No definition available.

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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.

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- Definition

Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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- Definition

The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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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.

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Number of share options (or share units) exercised during the current period.

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