Unrecognized cost of unvested share-based compensation awards.

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)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

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.

+ 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 (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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).

+ 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 (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

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).

+ 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 (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of Banks in Compensation Peer Group

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Percentage

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Hold Period Before Vesting

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangement, Maximum Contractual Term

+ References

No definition available.

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Stock-Based Compensation Plans (Narrative) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended		9 Months Ended				0 Months Ended	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Stock Options [Member]	Sep. 30, 2013 Restricted Stock [Member]	Sep. 30, 2013 Non-Qualified Stock Options [Member]	Sep. 30, 2013 Incentive Stock Options [Member]	Feb. 20, 2013 Performance Based Restricted Stock Awards [Member]	Sep. 30, 2013 Performance Based Restricted Stock Awards [Member] bank	Sep. 30, 2013 Non-Vested Restricted Stock Awards [Member]	Sep. 30, 2013 Minimum [Member] Stock Options [Member]	Sep. 30, 2013 Minimum [Member] Restricted Stock [Member]	Sep. 30, 2013 Minimum [Member] Performance Based Restricted Stock Awards [Member]	Sep. 30, 2013 Maximum [Member] Stock Options [Member]	Sep. 30, 2013 Maximum [Member] Restricted Stock [Member]	Sep. 30, 2013 Maximum [Member] Performance Based Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Hold period before vesting	1 year
Vesting period								3 years		3 years	1 year		4 years	5 years
Maximum contractual term			10 years
Unrecognized compensation expense	$ 3.0
Weighted-average vesting period	1 year 8 months 0 days								1 year 10 months 24 days
Number of options outstanding	2,696,855	2,476,645			2,458,697	238,158
Shares authorized				100,000
Restricted stock shares granted during period				222,585			163,519	163,519
Vesting percentage								50.00%				0.00%			200.00%
Number of Banks in Compensation Peer Group								14
Unrecognized compensation cost									$ 10.7