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

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

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No definition available.

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

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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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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Loans and Allowance - Changes in Allowance for Loan Losses by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses:
Beginning balance				$ 80,552				$ 75,032	$ 80,552	$ 75,032	$ 66,037
Provision for losses	$ 500	$ 600	$ 500	1,200	$ 1,664	$ 1,400	$ 1,663	2,500	2,800	7,227	9,143
Recoveries on loans									3,553	6,276	4,880
Loans charged off									(6,621)	(7,983)	(5,028)
Ending balance	80,284				80,552				80,284	80,552	75,032
Commercial
Allowance for loan losses:
Beginning balance				32,657				30,420	32,657	30,420	27,698
Provision for losses									733	2,097	2,515
Recoveries on loans									1,244	2,456	1,590
Loans charged off									(1,732)	(2,316)	(1,383)
Ending balance	32,902				32,657				32,902	32,657	30,420
Commercial Real Estate
Allowance for loan losses:
Beginning balance				29,609				27,343	29,609	27,343	23,661
Provision for losses									1,555	2,482	3,159
Recoveries on loans									1,289	2,525	2,260
Loans charged off									(3,675)	(2,741)	(1,737)
Ending balance	28,778				29,609				28,778	29,609	27,343
Consumer
Allowance for loan losses:
Beginning balance				3,964				3,732	3,964	3,732	2,923
Provision for losses									239	679	1,078
Recoveries on loans									401	302	324
Loans charged off									(569)	(749)	(593)
Ending balance	4,035				3,964				4,035	3,964	3,732
Residential
Allowance for loan losses:
Beginning balance				$ 14,322				$ 13,537	14,322	13,537	11,755
Provision for losses									273	1,969	2,391
Recoveries on loans									619	993	706
Loans charged off									(645)	(2,177)	(1,315)
Ending balance	$ 14,569				$ 14,322				$ 14,569	$ 14,322	$ 13,537