Borrowed Funds - Contractual Maturities of FHLB Advances and Reverse Repurchase Agreements (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLB Advances, 2019	$ 280,077
FHLB Advances, 2020	89,770
FHLB Advances, 2021	24,743
FHLB Advances, 2022	54,793
FHLB Advances, 2023	0
FHLB Advances contractual maturities, net	449,383	$ 288,691
Reverse Repurchase Agreements
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
2019	61,760
2020	0
2021	0
2022	0
2023	0
Contractual maturities, net	$ 61,760

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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