Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended	9 Months Ended
Aug. 23, 2013 Imperial's landscape nursery business	Aug. 31, 2013 Property and inventory purchase commitments
Commitments and Contingencies
Purchase obligations		$ 903
Period over which sale consideration is to be received	36 months

Represents the period of time over which sale consideration is to be received by the entity.

No definition available.

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Namespace Prefix:	grif_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration