Chapter 11 Proceedings and Emergence - Reorganization Items - Interest Expense (Details) $ in Millions	2 Months Ended
Dec. 07, 2023 USD ($)
Chapter 11 Proceedings and Emergence
Interest expense related to prepetition LSTC	$ 1.4

Amount of reorganization items related to interest expense related to entities in bankruptcy.

No definition available.

Name:	cgrn_DebtorReorganizationItemsInterestExpense
Namespace Prefix:	cgrn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration