Earnings (Loss) Per Share - Narrative (Details)	Apr. 03, 2022
Earnings Per Share [Abstract]
Nonvested restricted shares right to receive dividends, per share ratio to common shares	1

Participating Nonvested Shares With Non-Forfeitable Dividend Rights, Ratio To Common Shares

No definition available.

Name:	frgi_ParticipatingNonvestedSharesWithNonForfeitableDividendRightsRatioToCommonShares
Namespace Prefix:	frgi_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant