ALLL Activity (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Allowance for loan and lease losses
Balance at beginning of period	$ 131,239	$ 129,568
Provision for loan losses	57	795
Charge-offs	(3,341)	(5,007)
Recoveries	1,831	2,252
Balance at end of period	129,786	127,608
Residential Real Estate \| Residential Real Estate
Allowance for loan and lease losses
Balance at beginning of period	10,631	10,798
Provision for loan losses	278	(177)
Charge-offs	(292)	(3)
Recoveries	94	16
Balance at end of period	10,711	10,634
Commercial \| Commercial Real Estate
Allowance for loan and lease losses
Balance at beginning of period	72,448	68,515
Provision for loan losses	(148)	245
Charge-offs	(283)	(1,033)
Recoveries	311	615
Balance at end of period	72,328	68,342
Commercial \| Other Commercial
Allowance for loan and lease losses
Balance at beginning of period	38,160	39,303
Provision for loan losses	(915)	(3)
Charge-offs	(840)	(1,788)
Recoveries	444	596
Balance at end of period	36,849	38,108
Consumer and Other \| Home Equity
Allowance for loan and lease losses
Balance at beginning of period	5,811	6,204
Provision for loan losses	64	(202)
Charge-offs	(8)	(12)
Recoveries	13	50
Balance at end of period	5,880	6,040
Consumer and Other \| Other Consumer
Allowance for loan and lease losses
Balance at beginning of period	4,189	4,748
Provision for loan losses	778	932
Charge-offs	(1,918)	(2,171)
Recoveries	969	975
Balance at end of period	$ 4,018	$ 4,484

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

+ Details

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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.

+ Details

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

+ Details

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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