Fair Value Measurements and Fair Values of Financial Instruments - Additional Information (Detail)	6 Months Ended
Jun. 30, 2016 USD ($) Company	Dec. 31, 2015 USD ($)
Fair Value Disclosures [Abstract]
Impaired loans, recorded investment	$ 8,007,000	$ 9,548,000
Impaired loans with an allowance recorded, recorded investment	457,000	1,124,000
Impaired loans valuation allowance	36,000	$ 715,000
Impairment of goodwill	0
Goodwill acquired	$ 651,000
Number of wealth management companies acquired \| Company	2

No definition available.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of allowance for credit losses related to recorded investment.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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The number of businesses acquired by the entity during the period.

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