Deposits - Total Deposits (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Banking and Thrift [Abstract]
Percentage Change, Checking, non-interest bearing	8.10%
Percentage Change, Checking, interest bearing	4.70%
Percentage Change, Savings accounts	(1.60%)
Percentage Change, Certificates of deposit	3.80%
Percentage change, Total	2.10%
Checking, non-interest bearing	$ 313,543	$ 289,922
Checking, interest bearing	569,087	543,388
Savings accounts	938,342	953,438
Certificates of deposit	239,638	230,774
Total deposits	$ 2,060,610	$ 2,017,522

Certificate of Deposit Increase (Decrease), Percentage

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- Definition

Deposits Increase (Decrease), Percentage.

+ References

No definition available.

+ Details

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- Definition

Interest Bearing Checking Deposit Increase (Decrease), Percentage.

+ References

No definition available.

+ Details

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- Definition

Non Interest Bearing Checking Deposit Increase (Decrease), Percentage.

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No definition available.

+ Details

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- Definition

Saving Accounts Deposit Increase (Decrease), Percentage

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No definition available.

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- References

No definition available.

+ Details

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Amount of interest-bearing domestic certificate of deposit liabilities.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic checking deposit liabilities.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

+ References

+ Details

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- Definition

The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

+ References

+ Details

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