Securities (Detail 3) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Available-for-sale securities
Impairment losses recognized in earnings on other-than-temporarily impaired securities	$ 271	$ 248	$ 336	$ 248
Impairment losses, net of tax, recognized in other comprehensive loss on other-than-temporarily impaired securities	211	184	211	184
Impairment losses recognized in earnings income for securities held- to-maturity	0	0	0	0
Total debt securities
Changes in cumulative credit related other-than-temporary impairment recognized in earnings
Balance, beginning of period	2,535	4,549	2,470	4,549
Subsequent credit-related impairment	52	248	117	248
Reduction for securities sold or redeemed		(2,402)		(2,402)
Balance, end of period	2,587	2,395	2,587	2,395
CMOs - Non-agency
Available-for-sale securities
Impairment losses recognized in earnings on other-than-temporarily impaired securities	52	$ 248	117	$ 248
Equity Securities
Available-for-sale securities
Impairment losses recognized in earnings on other-than-temporarily impaired securities	$ 219		$ 219

Accumulated other comprehensive loss related to portion of other than temporary impairment (OTTI) due to factors other than credit losses on debt securities categorized as held-to-maturity that an entity does not intend to sell and which it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis of the debt security. The amount represented by this item is net of tax, as applicable.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

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

-Publisher FASB

-Name Accounting Standards Codification

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

+ References

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

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

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- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

+ References

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Amount after tax of other than temporary impairment (OTTI) loss on investment in available-for-sale debt security, recognized in other comprehensive loss.

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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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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