Fair Value Measurements - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Fair Value Disclosures [Abstract]
Decrease in other expenses due to one percent increase in discount rate	$ 0.1
Increase in other expenses due to one percent decrease in discount rate	$ 0.1

Sensitivity Analysis Of Fair Value, Contingent Consideration, Impact Of One Percent Decrease In Discount Rate On Other Expenses

No definition available.

Name:	acel_SensitivityAnalysisOfFairValueContingentConsiderationImpactOfOnePercentDecreaseInDiscountRateOnOtherExpenses
Namespace Prefix:	acel_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration