Derivative Financial Instruments - Summary of Instruments (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)	$ 1,877
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)		$ (56)	$ (184)
Interest rate products \| Interest income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)	1,877
Amount of (Loss) or Gain Recognized in OCI on Derivative (Effective Portion)		(56)	(184)
Derivatives not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) or Gain Recognized in Income	40	(364)	(306)
Derivatives not designated as hedging instruments \| Interest rate lock commitments with customers \| Mortgage banking activities, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) or Gain Recognized in Income	1,399	(28)	680
Derivatives not designated as hedging instruments \| Forward sale commitments \| Mortgage banking activities, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) or Gain Recognized in Income	$ (1,359)	$ (336)	$ (986)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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