Interest from Counterparty

No definition available.

Name:	aaon_InterestFromCounterparty
Namespace Prefix:	aaon_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Loans and Leases Receivable, Gross, Interest Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	aaon_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Loans and Leases Receivable, Gross, Term

+ References

No definition available.

+ Details

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Namespace Prefix:	aaon_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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-Publisher FASB
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-Topic 230
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

+ Details

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

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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+ Details

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

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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+ Details

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

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 14
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

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

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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New Market Tax Credit (Details) - USD ($)		9 Months Ended
New Market Tax Credit (Details) - USD ($)	Oct. 24, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Line of Credit Facility [Line Items]
Due to related parties		$ 0		$ 2,000
Amortization of debt issuance costs		31,000	$ 0
Subsidiary
Line of Credit Facility [Line Items]
Due to related parties	$ 22,500,000
Investor
Line of Credit Facility [Line Items]
Loans receivable	$ 15,900,000
Loans receivable, term	25 years
Loans receivable, interest rate	1.00%
Proceeds from debt	$ 15,900,000
Interest from counterparty	6,300,000
Debt issuance costs	300,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Credit facility maximum borrowings	$ 23,000,000.0	$ 30,000,000.0