Assumption of percentage of restricted stock units issued for calculations.

No definition available.

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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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Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Number of warrants or rights outstanding.

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Unrecognized cost of unvested share-based compensation awards.

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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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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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No definition available.

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Period 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, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made 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).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

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Stock Incentive Plans - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Jun. 16, 2009	Apr. 06, 2013	Jan. 01, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards issued	0	0
Common stock shares available under incentive compensation plans	2,122,522
Unrecognized compensation cost related to unvested restricted stock awards	$ 4,509
Stock options exercised	60,094	87,332
Intrinsic value of outstanding and exercisable stock options	1,890
Common shares available for purchase under warrants			651,042
Parkvale Financial Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued	819,640
Annapolis Bancorp, Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price	$ 3.32
Warrant issued	342,564
Warrants converted to purchase common stock	367,916
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense related to restricted stock awards	340	532
Tax benefit related to restricted stock awards	119	186
Total fair value of awards vested	5,740	8,631
Unrecognized compensation cost related to unvested restricted stock awards	4,509
Amount subject to accelerated vesting under Incentive Compensation Plan	20
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised	60,094	59,217
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for purchase under warrants	1,302,083
Warrant Expires In 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price	$ 11.52
Warrant Expires In 2019 [Member] \| Annapolis Bancorp, Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price				$ 3.57
Service-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards issued, years	3 years
Unrecognized compensation cost related to unvested restricted stock awards	2,659
Performance-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards issued, years	3 years
Unrecognized compensation cost related to unvested restricted stock awards	$ 1,850
Warrant Expires in 2018 [Member] \| Parkvale Financial Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price					$ 5.81
Market Based Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock percentage of number of units issued	100.00%