Name:	ttek_BusinessCombinationAcquisitionAndIntegrationRelatedCosts
Namespace Prefix:	ttek_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Professional service costs incurred for acquisition and integration of other business entity.

No definition available.

Name:	ttek_BusinessCombinationProfessionalServiceCost
Namespace Prefix:	ttek_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of real estate related costs incurred for acquisition of other business entity.

No definition available.

Name:	ttek_BusinessCombinationRealEstateRelatedCosts
Namespace Prefix:	ttek_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents severance including change in control payments as part of acquisition and integration expenses.

No definition available.

Name:	ttek_BusinessCombinationSeveranceIncludingChangeInControlPayments
Namespace Prefix:	ttek_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash outflow during the period associated with acquisition and integration-related costs resulting from a business combination.

No definition available.

Name:	ttek_CashPaidToAcquireBusinessesAcquisitionAndIntegrationCosts
Namespace Prefix:	ttek_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents pre-payment charges paid for early closure of debt.

No definition available.

Name:	ttek_DebtPrePaymentChargesPaid
Namespace Prefix:	ttek_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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.

No definition available.