Allowance for Loan Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	$ 4,757	$ 4,643
Financing Receivable, Allowance for Credit Losses, Charge-offs	(168)	(596)
Financing Receivable, Allowance for Credit Losses, Recoveries	201	1,010
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	33	414
Provision for loan losses	0	(300)
Financing Receivable, Allowance for Credit Losses	4,790	4,757
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	653	540
Financing Receivable, Allowance for Credit Losses, Charge-offs	(52)	(449)
Financing Receivable, Allowance for Credit Losses, Recoveries	70	461
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	18	12
Provision for loan losses	107	101
Financing Receivable, Allowance for Credit Losses	778	653
Construction And Land Development Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	734	812
Financing Receivable, Allowance for Credit Losses, Charge-offs	0	0
Financing Receivable, Allowance for Credit Losses, Recoveries	0	347
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	0	347
Provision for loan losses	(34)	(425)
Financing Receivable, Allowance for Credit Losses	700	734
Commercial Real Estate Loans, Total [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	2,126	2,071
Financing Receivable, Allowance for Credit Losses, Charge-offs	(38)	0
Financing Receivable, Allowance for Credit Losses, Recoveries	19	0
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(19)	0
Provision for loan losses	111	55
Financing Receivable, Allowance for Credit Losses	2,218	2,126
Residential Real Estate Loans, Total [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	1,071	1,107
Financing Receivable, Allowance for Credit Losses, Charge-offs	(26)	(107)
Financing Receivable, Allowance for Credit Losses, Recoveries	79	115
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	53	8
Provision for loan losses	(178)	(44)
Financing Receivable, Allowance for Credit Losses	946	1,071
Consumer Installment and Revolving Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	173	113
Financing Receivable, Allowance for Credit Losses, Charge-offs	(52)	(40)
Financing Receivable, Allowance for Credit Losses, Recoveries	33	87
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(19)	47
Provision for loan losses	(6)	13
Financing Receivable, Allowance for Credit Losses	$ 148	$ 173

No definition available.

Name:	aubn_FinancingReceivableAllowanceForCreditLossesNetChargeoffsRecoveries
Namespace Prefix:	aubn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

+ Details

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

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

Name:	us-gaap_ProvisionForLoanLeaseAndOtherLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=aubn_CommercialAndIndustrialLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=aubn_ConstructionAndLandDevelopmentLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=aubn_CommercialRealEstateLoansTotalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=aubn_ResidentialRealEstateLoansTotalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=aubn_ConsumerInstallmentAndRevolvingLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: