The average holding size, aggregate value, of the securities in the municipal bond portfolio.

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Number of pooled trust preferred securities carried by the entity.

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Number of single issuer trust preferred securities carried by the entity.

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Schedule Of Securities [Line Items]

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The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged to secure public deposits, trust deposits and for other purposes as required by law.

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No definition available.

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Amortized cost of single issuer trust preferred securities carried by the entity.

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Fair value of single issuer trust preferred securities carried by the entity.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

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The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

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-Subparagraph (SX 210.9-04.13(h))

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-Section S99

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-Subparagraph (SX 210.7-04.3)

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Bonds or similar securities issued by state, city, or local governments or the agencies operated by state, city, or local governments which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

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Securities - Additional Information (Detail) $ in Thousands	3 Months Ended			6 Months Ended
Securities - Additional Information (Detail) $ in Thousands	Jun. 30, 2015 USD ($) Security	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($) Securities	Jun. 30, 2015 USD ($) Security	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Schedule Of Securities [Line Items]
Number of pooled issue securities \| Securities			23
Net proceeds from sale of securities				$ 33,228	$ 150,055
Net securities (losses) gains	$ 14	$ 776		5	10,237
Securities pledged to secure public deposits, trust deposits and for other purposes, carrying value	1,961,096			1,961,096		$ 1,036,380
Securities pledged as collateral for short-term borrowings, carrying value	$ 240,738			$ 240,738		$ 892,647
Number of single-issuer securities \| Security	4			4
Estimated fair value of single-issue trust preferred securities	$ 6,150			$ 6,150
Amortized cost of single-issue trust preferred securities	6,892			6,892
Impairment losses on securities				0	$ 0
Municipal bond portfolio, value	$ 206,022			206,022
Municipal Debt Securities [Member] \| Weighted Average [Member]
Schedule Of Securities [Line Items]
Average holding size of securities in bond portfolio				$ 1,355
Municipal Debt Securities [Member] \| Combined A Rating [Member] \| Minimum [Member]
Schedule Of Securities [Line Items]
Percentage of portfolio				99.00%
Municipal Debt Securities [Member] \| General Obligation Bonds [Member]
Schedule Of Securities [Line Items]
Percentage of portfolio				99.60%
Municipal Debt Securities [Member] \| Pennsylvania, Ohio and Maryland [Member]
Schedule Of Securities [Line Items]
Percentage of portfolio				92.50%
Municipal Debt Securities [Member] \| Capital Support Agreement [Member]
Schedule Of Securities [Line Items]
Percentage of portfolio				84.00%
Pooled TPS [Member]
Schedule Of Securities [Line Items]
Net proceeds from sale of securities			$ 51,540
Net securities (losses) gains			13,766
Other Securities [Member]
Schedule Of Securities [Line Items]
Net securities (losses) gains			$ (3,529)