Interest from Counterparty

No definition available.

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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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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

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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

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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

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-Publisher FASB
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Balance Type:	credit
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- 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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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

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Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=aaon_Investor1Member
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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New Markets Tax Credit (Details) - USD ($)		12 Months Ended
New Markets Tax Credit (Details) - USD ($)	Oct. 24, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Proceeds from financing obligation, net of issuance costs		$ 6,614,000	$ 0	$ 0
Due to affiliates		2	0
Debt issuance costs		7,000	$ 0	$ 0
Subsidiary
Line of Credit Facility [Line Items]
Due to affiliates	$ 22,500,000
Investor
Line of Credit Facility [Line Items]
Loans and leases receivable	$ 15,900,000
Loans and leases receivable, term	25 years
Loans and leases receivable, interest rate	1.00%
Proceeds from financing obligation, net of issuance costs	$ 15,900,000
Interest	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