Balance Sheet Offsetting - Financial Instruments Eligible for Offset Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Gross Amount Recognized, Derivatives, Financial Assets	$ 20,847	$ 5,266
Gross Amount Offset, Derivatives, Financial assets	0	0
Net Amount Recognized, Derivatives, Financial assets	20,847	5,266
Gross Amount Recognized, Resell agreements, Financial assets	20,000	31,299
Gross Amount Offset, Resell agreements, Financial assets	0	0
Net Amount Recognized, Resell agreements, Financial assets	20,000	31,299
Gross Amount Recognized, Financial assets	40,847	36,565
Gross Amount Offset, Financial assets	0	0
Net Amount Recognized, Financial assets	40,847	36,565
Gross Amount Recognized, Derivatives, Financial Liabilities	52,153	26,640
Gross Amount Offset, Derivatives, Financial liabilities	0	0
Net Amount Recognized, Derivatives, Financial liabilities	52,153	26,640
Gross Amount Recognized, Repurchase agreements, Financial liabilities	1,574,367	1,668,142
Gross Amount Offset, Repurchase agreements, Financial liabilities	0	0
Net Amount Recognized, Repurchase agreements, Financial liabilities	1,574,367	1,668,142
Gross Amount Recognized, Financial liabilities	1,626,520	1,694,782
Gross Amount Offset, Financial liabilities	0	0
Net Amount Recognized, Financial Liabilities	1,626,520	1,694,782
Loan/lease interest rate swaps and caps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Gross Amount Recognized, Derivatives, Financial Assets	1,197	339
Gross Amount Offset, Derivatives, Financial assets	0	0
Net Amount Recognized, Derivatives, Financial assets	1,197	339
Commodity swaps and options [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Gross Amount Recognized, Derivatives, Financial Assets	19,650	4,927
Gross Amount Offset, Derivatives, Financial assets	0	0
Net Amount Recognized, Derivatives, Financial assets	19,650	4,927
Gross Amount Recognized, Derivatives, Financial Liabilities	15,011	6,986
Gross Amount Offset, Derivatives, Financial liabilities	0	0
Net Amount Recognized, Derivatives, Financial liabilities	15,011	6,986
Foreign currency forward contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Gross Amount Recognized, Derivatives, Financial Assets	0
Gross Amount Offset, Derivatives, Financial assets	0
Net Amount Recognized, Derivatives, Financial assets	0
Gross Amount Recognized, Derivatives, Financial Liabilities	0	33
Gross Amount Offset, Derivatives, Financial liabilities	0	0
Net Amount Recognized, Derivatives, Financial liabilities	0	33
Loan/lease interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Gross Amount Recognized, Derivatives, Financial Liabilities	37,142	19,621
Gross Amount Offset, Derivatives, Financial liabilities	0	0
Net Amount Recognized, Derivatives, Financial liabilities	$ 37,142	$ 19,621

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Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

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Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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