Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2013	Apr. 01, 2012	Mar. 31, 2013	Apr. 01, 2012
Condensed Consolidated Statements of Comprehensive Income
Net income including noncontrolling interests	$ 24,872	$ 22,321	$ 51,268	$ 45,024
Other comprehensive (loss) income:
Foreign currency translation adjustments, net of tax	(12,154)	9,357	(17,767)	20,185
Foreign currency hedge, net of tax	(28)	(12)	93	(214)
Other comprehensive (loss) income	(12,182)	9,345	(17,674)	19,971
Comprehensive income including noncontrolling interests	12,690	31,666	33,594	64,995
Net income attributable to noncontrolling interests	(52)	(37)	(225)	(130)
Foreign currency translation adjustments, net of tax	20	(14)	33	(14)
Comprehensive income attributable to noncontrolling interests	(32)	(51)	(192)	(144)
Comprehensive income attributable to Tetra Tech	$ 12,658	$ 31,615	$ 33,402	$ 64,851

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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