Derivatives and Hedging Fair Value of Derivative Contracts (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	$ 542	$ 125	$ 346
Derivative Liability, Fair Value	511	99	230
Derivative, Notional Amount	27,881	9,643	27,499
Not Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	249	81	83
Derivative Liability, Fair Value	249	81	83
Derivative, Notional Amount	2,932	2,932	2,348
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	293	44	263
Derivative Liability, Fair Value	262	18	147
Derivative, Notional Amount	24,949	6,711	25,151
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	5,966	1,778	1,436
Derivative Liability, Fair Value	101,315	55,471	62,754
Notional Amount, Netting Adjustments	0	0	0
Derivative Netting Adjustments	0	21	163
Derivative, Notional Amount	856,948	862,952	958,298
Positive NPVs	5,966	1,757	1,273
Negative NPVs	101,315	55,450	62,591
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value	5,966	1,778	1,436
Derivative Liability, Fair Value	101,315	55,471	62,754
Derivative, Notional Amount	$ 856,948	$ 862,952	$ 958,298

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payment on derivative.

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