Name:	alrs_NetProcessingFeesToBeReceived
Namespace Prefix:	alrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the number of clients assisted under the payment protection program (PPP).

No definition available.

Name:	alrs_NumberOfClientsAssistedUnderPaymentProtectionProgram
Namespace Prefix:	alrs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Processing fees percentage to be received under the payment protection program.

No definition available.

Name:	alrs_ProcessingFeePercentageUnderPaymentProtectionProgram
Namespace Prefix:	alrs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Threshold value loans financed under the payment protection program.

No definition available.

Name:	alrs_ThresholdValueLoansFinancedUnderPaymentProtectionProgram
Namespace Prefix:	alrs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

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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.

No definition available.

Name:	us-gaap_UnusualOrInfrequentItemLineItems
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Data Type:	xbrli:stringItemType
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Namespace Prefix:
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Balance Type:
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Name:	us-gaap_LoansInsuredOrGuaranteedByGovernmentAuthoritiesAxis=alrs_LoansFinancingLessThanThreeHundredFiftyThousandMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_LoansInsuredOrGuaranteedByGovernmentAuthoritiesAxis=alrs_LoansFinancingThreeHundredFiftyThousandToTwoMillionMember
Namespace Prefix:
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Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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