Accumulated Other Comprehensive Loss - Reclassifications from Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities (gains) losses reclassified into earnings	$ (8)	$ 55
Related income tax expense (benefit)	2,353	956
Total reclassifications	(5,907)	(2,655)
Amount Reclassified from Accumulated Other Comprehensive Loss [Member] \| Securities Available for Sale [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities (gains) losses reclassified into earnings	(8)	55
Related income tax expense (benefit)	3	(19)
Total reclassifications	$ (5)	$ 36

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.

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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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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