Fair Value Measurements - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Fair Value Disclosures [Abstract]
Decrease in other expenses due to one percent increase in discount rate	$ 0.2
Increase in other expenses due to one percent decrease in discount rate	$ 0.2

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

No definition available.

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