Acquisition - Carrying Value of Acquired Loans (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Book value of loans acquired	$ 1,311,669	$ 1,635,802
Accretion recorded on acquired loans year to date	4,903	966
Accretion recorded on acquired unfunded commitments year to date	670	74
West Suburban Bancorp, Inc
Business Acquisition [Line Items]
Book value of loans acquired	1,249,425	1,521,161
Abc Bank
Business Acquisition [Line Items]
Book value of loans acquired	46,196	68,783
Talmer Bank
Business Acquisition [Line Items]
Book value of loans acquired	16,048	45,858
PCD
Business Acquisition [Line Items]
Book value of loans acquired	79,662	106,956
Accretion recorded on acquired loans year to date	782	401
PCD \| West Suburban Bancorp, Inc
Business Acquisition [Line Items]
Book value of loans acquired	77,548	102,409
PCD \| Abc Bank
Business Acquisition [Line Items]
Book value of loans acquired	2,114	4,547
Non-PCD
Business Acquisition [Line Items]
Book value of loans acquired	1,232,007	1,528,846
Accretion recorded on acquired loans year to date	4,121	565
Non-PCD \| West Suburban Bancorp, Inc
Business Acquisition [Line Items]
Book value of loans acquired	1,171,877	1,418,752
Non-PCD \| Abc Bank
Business Acquisition [Line Items]
Book value of loans acquired	44,082	64,236
Non-PCD \| Talmer Bank
Business Acquisition [Line Items]
Book value of loans acquired	$ 16,048	$ 45,858

Amount of increase (decrease) of the excess of a unfunded commitment's cash flows expected to be collected over the investor's initial investment in acquired unfunded commitments not accounted for as debt securities with evidence of deterioration of credit quality.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of increase (decrease) of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=123409700&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=123409700&loc=d3e13503-111538

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