Securities - Debt Securities Held to Maturity by Contractual Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Investments Debt And Equity Securities [Abstract]
Due in one year or less, amortized cost	$ 3,000
Due after one year through five years, amortized cost	635
Due after five years through ten years, amortized cost	9,408
MBS, amortized cost	62,717
Held to maturity securities, Total amortized cost	75,760	$ 77,491
Due in one year or less, fair value	3,006
Due after one year through five years, fair value	640
Due after five years through ten years, fair value	9,497
MBS, fair value	61,605
Held to maturity securities, Total fair value	$ 74,748	$ 75,075

Amount of investment in debt security measured at amortized cost (held-to-maturity).

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-Publisher FASB
-Name Accounting Standards Codification
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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Amortized cost of investment in debt security measured at amortized cost (held-to-maturity), without single maturity date and not allocated over maturity grouping.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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