Investment Maturity Term

No definition available.

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- Definition

Marketable Security, Debt Instrument, Monthly Principal Payment

+ References

No definition available.

+ Details

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Namespace Prefix:	acel_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Rate of interest on investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Cost of the investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

+ Details

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

- Definition

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580

+ Details

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

- 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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Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Investment in Convertible Notes (Details) - USD ($)			3 Months Ended
Investment in Convertible Notes (Details) - USD ($)	Oct. 11, 2019	Jul. 19, 2019	Mar. 31, 2021	Mar. 31, 2020	Mar. 09, 2021	Jul. 30, 2020
Debt Securities, Available-for-sale [Line Items]
Monthly installment receivable	$ 1,000,000
Unrealized gain on investment in convertible notes, net			$ 469,000	$ 0
Convertible Promissory Notes
Debt Securities, Available-for-sale [Line Items]
Investment purchase	$ 25,000,000.0	$ 30,000,000.0			$ 25,000,000.0	$ 25,000,000.0
Investment interest rate		3.00%
Convertible Promissory Notes \| Subordinated Debt
Debt Securities, Available-for-sale [Line Items]
Investment purchase		$ 5,000,000.0			$ 5,000,000.0	$ 5,000,000.0
Investment maturity		6 months