Allowance for Credit Losses and Credit Quality of Loans, Changes in Allowance for Loan Losses by Portfolio Segment (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	$ 72,505
Charge-offs	(8,454)
Recoveries	1,547
Provision	5,807
Balance, end of period	71,405
Commercial Loans [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	32,759
Charge-offs	(747)
Recoveries	94
Provision	53
Balance, end of period	32,159
Consumer Loans [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	37,178
Charge-offs	(7,433)
Recoveries	1,399
Provision	5,660
Balance, end of period	36,804
Residential Real Estate [Member]
Changes in allowance for loan losses by portfolio segment [Roll Forward]
Balance, beginning of period	2,568
Charge-offs	(274)
Recoveries	54
Provision	94
Balance, end of period	$ 2,442

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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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.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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