Branch Sales

No definition available.

Name:	asb_BranchSales
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- Definition

Gain (Loss) on Sale and Maturity of Other Investments, Before Tax

+ References

No definition available.

+ Details

Name:	asb_GainLossOnSaleAndMaturityOfOtherInvestmentsBeforeTax
Namespace Prefix:	asb_
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Balance Type:	credit
Period Type:	duration

- Definition

Number of acquisitions

+ References

No definition available.

+ Details

Name:	asb_NumberOfAcquisitions
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Period Type:	duration

- Definition

Purchase premium on deposits transferred

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
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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.

+ Details

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

+ Details

Name:	us-gaap_Deposits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Data Type:	na
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Period Type:

Acquisitions (Details Textuals) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
Acquisitions (Details Textuals) $ in Thousands	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($) branch	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) branch	Mar. 01, 2021 USD ($)	Feb. 26, 2021 USD ($) percent branch
Business Acquisition [Line Items]
Number of acquisitions \| branch		0		0
Branch Sales \| branch						1
Deposits		$ 28,576,577		$ 28,466,430		$ 31,000
Business Combination, Acquired Receivables, Gross Contractual Amount						$ 0
Purchase premium on deposits transferred \| percent						0.04
Whitnell
Business Acquisition [Line Items]
Disposal Group, Including Discontinued Operation, Consideration					$ 8,000
Gain (Loss) on Sale and Maturity of Other Investments, Before Tax	$ 2,000		$ 2,000