Supplemental Cash Flow Disclosures - Non-cash Investing and Financing Activities (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash paid during the period for:
Interest	$ 4,004us-gaap_InterestPaid	$ 5,108us-gaap_InterestPaid
Income Taxes Paid, Net	1,500us-gaap_IncomeTaxesPaidNet	0us-gaap_IncomeTaxesPaidNet
Non-cash investing and financing activities:
Loans Transferred to Other Real Estate Owned and Repossessions	797	1,292
Fair value of loans transferred from held to maturity to held for sale	3,011	716
Gross increase in market value adjustment to securities available for sale	9,869	12,459
Gross increase in market value adjustment to derivatives	1,200	0
Investments committed to purchase not settled	637	2,522
Unsettled treasury stock repurchases	$ 453fcf_Unsettledtreasurystockrepurchases	$ 233fcf_Unsettledtreasurystockrepurchases

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Gross Increase in Market Value Adjustment to Derivatives

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- Definition

Gross increase in market value adjustment to securities available for sale.

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No definition available.

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- Definition

Loans Transferred to Other Real Estate Owned and Repossessions

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No definition available.

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- Definition

Unsettled treasury stock repurchases

+ References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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- Definition

The amount of cash paid for interest during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

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- Definition

The amount of investments that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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