Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Loans and Leases (Summary Of The Recorded Investment Of Company's TDRs) (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	$ 243,067		$ 230,414
Specific reserves for TDRs included in the balance of ALLL	211,671	$ 211,389	212,353	$ 207,322	$ 205,349	$ 199,994
Additional funds committed to borrowers in TDR status	6,160		3,893
Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	136,081		138,479
Nonperforming Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	106,986		91,935
Nonperforming Financial Instruments [Member] \| Troubled Debt Restructures [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDRs included in the balance of ALLL	$ 14,368		$ 11,930