Represents the amount of attorneys' fees and costs assessed by the court in a legal matter.

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Namespace Prefix:	ttek
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Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of compensatory damages assessed by a jury.

+ Details

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

- Definition

Represents the amount of punitive damages assessed by a jury.

+ Details

Name:	ttek_LossContingencyPunitiveDamagesAssessed
Namespace Prefix:	ttek
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of compensatory damages as reduced upon appeal.

+ Details

Name:	ttek_LossContingencyReducedCompensatoryDamages
Namespace Prefix:	ttek
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of punitive damages as reduced upon appeal.

+ Details

Name:	ttek_LossContingencyReducedPunitiveDamages
Namespace Prefix:	ttek
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of a bond posted by the defendant as required by the court in a legal matter.

+ Details

Name:	ttek_LossContingencySettlementAgreementConsiderationBond
Namespace Prefix:	ttek
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
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- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10, 11, 12

+ Details

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- Definition

The estimated minimum amount of possible loss from the contingency.

+ References

+ Details

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Commitments and Contingencies (Details) (Lawsuit for misappropriation of trade secrets, USD $) In Millions	1 Months Ended			9 Months Ended
	Dec. 27, 2009	Jul. 31, 2008 AMT	Dec. 30, 2007 AMT	Jul. 03, 2011 AMT
Loss contingencies
Assessed compensatory damages			$ 5.8
Assessed punitive damages			17
Compensatory damages		2.0
Punitive damages		5.8
Attorneys' fees and costs	2.9
Value of bond posted as required by trial court				13.4
Reasonably possible loss exposure including attorneys' fees, low end of range				0
Reasonably possible loss exposure including attorneys' fees, high end of range				$ 14.5