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Additional restiction for vesting of restricted stock. The stock that has otherwise vested for the passage of time may not become transferable at any time earlier than as permitted under the schedule set forth by TARP, which is based on the repayment in 25% increments of the aggregate financial assistance received from the U.S. Department of Treasury.

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For purpose of comupting the discount, the Corporation estimated a percentage in the value of the common stock and assumed a holding period.

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Percentage of restricted stock vested during the period that was previously subject to tarp requirements.

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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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Unrecognized cost of unvested share-based compensation awards.

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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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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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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).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Value of stock related to Restricted Stock Awards forfeited during the period.

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Number of shares that have been repurchased during the period and are being held in treasury.

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STOCK-BASED COMPENSATION - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	May 24, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock issued on the employees		1,925,575
Stock Issued During Period Value Restricted Stock Award Forfeitures		$ 0.1	$ 0.1	$ 0.1
Treasury Stock Shares Acquired		291,759	222,381
Maximum [Member] \| Board Of Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock vesting period		5 years
Senior Executives [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted shares		755,223	483,053
Share based compensation cost		$ 3.0	$ 2.3
Weighted-Average Grant Date Fair Value, Granted restricted stock		$ 3.96	$ 4.67
Treasury Stock Shares Acquired		226,261	149,463
Omnibus Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Authorized granting up shares					14,169,807
Restricted stock available for issuance		6,846,986
Omnibus Plan [Member] \| Board Of Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock issued on the employees		130,873	219,531
Restricted stock vesting period		1 year
Omnibus Plan [Member] \| Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock issued on the employees		1,794,702	793,964
Omnibus Plan [Member] \| Maximum [Member] \| Board Of Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock vesting period			5 years
Omnibus Plan [Member] \| Maximum [Member] \| Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock vesting period		3 years	3 years
Omnibus Plan [Member] \| Minimum [Member] \| Board Of Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock vesting period			1 year
Omnibus Plan [Member] \| Minimum [Member] \| Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock vesting period		2 years	3 months
Troubled Asset Relief Program [Member] \| Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock issued on the employees		1,546,137
Percentage increments repayment under TARP		25.00%
Holding Period By The Us Treasury Of Outstanding Common Stock		2 years	1 year
Percentage Of Appreciation		14.00%	14.00%
Fair Value Of Restricted Stock Granted		$ 1.43	$ 3.18
Restricted Stock Vested Subject To Tarp Percentage	25.00%
Troubled Asset Relief Program [Member] \| U S Treasury And Government [Member] \| Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock issued on the employees			615,464
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation cost		$ 3.9	$ 3.8	$ 2.6
Number of vested shares		683,713
Stock based compensation expense unrecognized related to nonvested shares of restricted stock		$ 3.5
Period for cost recognition not yet recognized		1 year 3 months 18 days
Treasury Stock Shares Acquired		65,498	72,918
Restricted Stock [Member] \| Omnibus Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-Average Grant Date Fair Value, Granted restricted stock		$ 1.87