$TTEK
TETRA TECH INC Stock $ttek

$ttek Overview Financials Valuation SEC Filings Company Website

2019 Q3 Form 10-K Financial Statement

#000083164119000193 Filed on November 29, 2019

Income Statement

Concept	2019 Q3	2019 Q2	2019 Q1
Revenue	$841.5M	$825.8M	$722.6M
YoY Change	13.82%	17.93%
Cost Of Revenue	$532.7M	$505.2M	$488.9M
YoY Change	15.6%	14.45%
Gross Profit	$95.00M	$118.0M	$96.47M
YoY Change	-13.32%	29.05%
Gross Profit Margin	11.29%	14.29%	13.35%
Selling, General & Admin	$55.20M	$53.10M	$48.90M
YoY Change	2.41%	13.46%
% of Gross Profit	58.11%	45.0%	50.69%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$7.500M	$4.200M	$4.200M
YoY Change	53.06%	-17.65%
% of Gross Profit	7.89%	3.56%	4.35%
Operating Expenses	$56.20M	$53.20M	$48.90M
YoY Change	3.88%	9.24%
Operating Profit	$20.67M	$64.84M	$47.55M
YoY Change	-52.26%	51.8%
Interest Expense	-$4.000M	-$3.500M	-$3.200M
YoY Change	-6.98%	-14.63%
% of Operating Profit	-19.36%	-5.4%	-6.73%
Other Income/Expense, Net
YoY Change
Pretax Income	$16.60M	$61.30M	$44.38M
YoY Change	-67.55%	58.7%
Income Tax	$5.100M	$12.04M	-$11.56M
% Of Pretax Income	30.72%	19.65%	-26.05%
Net Earnings	$11.50M	$49.25M	$55.94M
YoY Change	-65.51%	71.33%
Net Earnings / Revenue	1.37%	5.96%	7.74%
Basic Earnings Per Share	$0.21	$0.90	$1.01
Diluted Earnings Per Share	$0.21	$0.88	$1.00
COMMON SHARES
Basic Shares Outstanding	54.62M shares	54.82M shares	55.14M shares
Diluted Shares Outstanding	55.62M shares	55.77M shares	55.99M shares

Balance Sheet

Concept	2019 Q3	2019 Q2	2019 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments	$120.7M	$111.2M	$130.7M
YoY Change	-43.6%	-45.28%
Cash & Equivalents	$120.7M	$111.2M	$130.7M
Short-Term Investments
Other Short-Term Assets	$62.20M	$123.8M	$72.00M
YoY Change	3.49%	90.17%
Inventory
Prepaid Expenses
Receivables	$768.7M	$729.0M	$629.6M
Other Receivables	$13.90M	$6.700M	$8.200M
Total Short-Term Assets	$1.080B	$1.116B	$998.4M
YoY Change	2.8%	-2.91%
LONG-TERM ASSETS
Property, Plant & Equipment	$39.44M	$40.07M	$41.66M
YoY Change	-8.87%	-27.79%
Goodwill	$924.8M	$851.6M	$827.7M
YoY Change	15.77%	5.18%
Intangibles	$16.44M	$10.44M	$11.70M
YoY Change	1.97%	-49.93%
Long-Term Investments	$6.873M	$7.655M	$3.536M
YoY Change	103.95%	141.71%
Other Assets	$51.66M	$39.59M	$38.29M
YoY Change	32.99%	12.79%
Total Long-Term Assets	$1.068B	$979.9M	$953.4M
YoY Change	17.44%	5.04%
TOTAL ASSETS
Total Short-Term Assets	$1.080B	$1.116B	$998.4M
Total Long-Term Assets	$1.068B	$979.9M	$953.4M
Total Assets	$2.147B	$2.096B	$1.952B
YoY Change	9.59%	0.65%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$206.6M	$179.2M	$135.4M
YoY Change	28.95%	15.42%
Accrued Expenses	$203.4M	$160.8M	$156.1M
YoY Change	41.15%	14.53%
Deferred Revenue	$165.6M	$147.5M	$154.6M
YoY Change	15.59%
Short-Term Debt	$0.00	$0.00	$24.70M
YoY Change
Long-Term Debt Due	$12.60M	$12.50M	$12.60M
YoY Change	-32.62%	-19.35%
Total Short-Term Liabilities	$770.0M	$646.9M	$624.4M
YoY Change	24.57%	15.52%
LONG-TERM LIABILITIES
Long-Term Debt	$263.9M	$324.1M	$231.3M
YoY Change	-37.01%	-30.08%
Other Long-Term Liabilities	$83.07M	$53.93M	$54.00M
YoY Change	43.99%	-1.65%
Total Long-Term Liabilities	$347.0M	$53.93M	$54.00M
YoY Change	501.47%	-1.65%
TOTAL LIABILITIES
Total Short-Term Liabilities	$770.0M	$646.9M	$624.4M
Total Long-Term Liabilities	$347.0M	$53.93M	$54.00M
Total Liabilities	$1.117B	$700.8M	$678.4M
YoY Change	65.28%	13.98%
SHAREHOLDERS EQUITY
Retained Earnings	$1.071B	$1.068B	$1.027B
YoY Change	13.36%	19.16%
Common Stock	$78.68M	$94.84M	$111.8M
YoY Change	-47.32%	-41.44%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$989.3M	$1.016B	$990.4M
YoY Change
Total Liabilities & Shareholders Equity	$2.147B	$2.096B	$1.952B
YoY Change	9.59%	0.65%

Cashflow Statement

Concept	2019 Q3	2019 Q2	2019 Q1
OPERATING ACTIVITIES
Net Income	$11.50M	$49.25M	$55.94M
YoY Change	-65.51%	71.33%
Depreciation, Depletion And Amortization	$7.500M	$4.200M	$4.200M
YoY Change	53.06%	-17.65%
Cash From Operating Activities	$95.10M	$14.20M	$114.5M
YoY Change	117.12%	-82.53%
INVESTING ACTIVITIES
Capital Expenditures	-$6.200M	-$2.800M	-$3.300M
YoY Change	264.71%	12.0%
Acquisitions
YoY Change
Other Investing Activities	-$48.80M	-$38.50M	$3.700M
YoY Change	-234.44%	-14.82%
Cash From Investing Activities	-$55.00M	-$41.30M	$300.0K
YoY Change	-259.42%	-13.42%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-87.80M	63.40M	-51.70M
YoY Change	39.37%	-2981.82%
NET CHANGE
Cash From Operating Activities	95.10M	14.20M	114.5M
Cash From Investing Activities	-55.00M	-41.30M	300.0K
Cash From Financing Activities	-87.80M	63.40M	-51.70M
Net Change In Cash	-47.70M	36.30M	63.10M
YoY Change	-411.76%	15.61%
FREE CASH FLOW
Cash From Operating Activities	$95.10M	$14.20M	$114.5M
Capital Expenditures	-$6.200M	-$2.800M	-$3.300M
Free Cash Flow	$101.3M	$17.00M	$117.8M
YoY Change	122.64%	-79.71%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--09-29
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0000831641
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CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.44
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.54
CY2018Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2018Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	150000000	shares
CY2019Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	150000000	shares
CY2018Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	55349000	shares
CY2019Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	54565000	shares
CY2018Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	55349000	shares
CY2019Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	54565000	shares
CY2018Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
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CY2019Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	2000000	shares
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CY2019Q3	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
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CY2019Q3	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2017	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	2100000	USD
CY2018	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	2500000	USD
CY2019	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	5200000	USD
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Annual Report DocumentAnnualReport	true
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-09-29
CY2019	dei	Document Transition Report DocumentTransitionReport	false
CY2019	dei	Entity File Number EntityFileNumber	0-19655
CY2019	dei	Entity Registrant Name EntityRegistrantName	TETRA TECH, INC.
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Pasadena
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	95-4148514
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	3475 East Foothill Boulevard
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	91107
CY2019	dei	City Area Code CityAreaCode	626
CY2019	dei	Local Phone Number LocalPhoneNumber	351-4664
CY2019	dei	Security12b Title Security12bTitle	Common Stock, $0.01 par value
CY2019	dei	Trading Symbol TradingSymbol	TTEK
CY2019	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2019	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2019	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2019	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2019	dei	Entity Small Business EntitySmallBusiness	false
CY2019	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019	dei	Entity Shell Company EntityShellCompany	false
CY2019Q1	dei	Entity Public Float EntityPublicFloat	3200000000	USD
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CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56598000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	57913000	shares
CY2019	us-gaap	Profit Loss ProfitLoss	158761000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	136957000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	117917000	USD
CY2019	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	-21109000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	-29656000	USD
CY2017	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	27894000	USD
CY2019	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	-12125000	USD
CY2018	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	806000	USD
CY2017	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	1614000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-33234000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-28850000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	29508000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-243000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	64000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-8000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	125770000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	108043000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	147433000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	125434000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	108033000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	147382000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	336000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	10000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	51000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	125770000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	108043000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	147433000	USD
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	869403000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	117917000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	27902000	USD
CY2017	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	1614000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	147433000	USD
CY2017	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	24000	USD
CY2017	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	21672000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	13450000	USD
CY2017	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	18564000	USD
CY2017	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-3470000	USD
CY2017	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	4940000	USD
CY2017	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	100000000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	928624000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	136957000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-29720000	USD
CY2018	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	806000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	108043000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	52000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	24477000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	19582000	USD
CY2018	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-8871000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	13511000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	5740000	USD
CY2018	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	75000000	USD
CY2018Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	967100000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	158761000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-20866000	USD
CY2019	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	-12125000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	125770000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	287000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	29674000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	17618000	USD
CY2019	us-gaap	Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures	-6893000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	11751000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	6846000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	100000000	USD
CY2018Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	-2767000	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	989464000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	158761000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	136957000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	117917000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	28844000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	38636000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	45756000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	25000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	568000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	647000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	17618000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	19582000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	13450000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-37615000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-29360000	USD
CY2017	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-9957000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	16964000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	7167000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	2847000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	7755000	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2017	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	ttek	Fair Value Adjustments To Contingent Consideration FairValueAdjustmentsToContingentConsideration	-1085000	USD
CY2018	ttek	Fair Value Adjustments To Contingent Consideration FairValueAdjustmentsToContingentConsideration	-4252000	USD
CY2017	ttek	Fair Value Adjustments To Contingent Consideration FairValueAdjustmentsToContingentConsideration	6923000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	232000	USD
CY2018	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-1045000	USD
CY2017	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	103000	USD
CY2019	ttek	Increase Decrease In Accounts Receivable And Contract With Customer Asset IncreaseDecreaseInAccountsReceivableAndContractWithCustomerAsset	10226000	USD
CY2018	ttek	Increase Decrease In Accounts Receivable And Contract With Customer Asset IncreaseDecreaseInAccountsReceivableAndContractWithCustomerAsset	46273000	USD
CY2017	ttek	Increase Decrease In Accounts Receivable And Contract With Customer Asset IncreaseDecreaseInAccountsReceivableAndContractWithCustomerAsset	64781000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-2568000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	12638000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	8317000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	39011000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-16032000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	18597000	USD
CY2019	ttek	Increase Decrease In Accrued Compensation IncreaseDecreaseInAccruedCompensation	18359000	USD
CY2018	ttek	Increase Decrease In Accrued Compensation IncreaseDecreaseInAccruedCompensation	27492000	USD
CY2017	ttek	Increase Decrease In Accrued Compensation IncreaseDecreaseInAccruedCompensation	13413000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	-6039000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	15228000	USD
CY2017	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	28298000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-16929000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	24998000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	5662000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	-11386000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	17596000	USD
CY2017	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	-13725000	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Operating Activities PaymentForContingentConsiderationLiabilityOperatingActivities	0	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Operating Activities PaymentForContingentConsiderationLiabilityOperatingActivities	2349000	USD
CY2017	us-gaap	Payment For Contingent Consideration Liability Operating Activities PaymentForContingentConsiderationLiabilityOperatingActivities	0	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	208513000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	185733000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	141487000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	16198000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9726000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9741000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	84159000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	68256000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	8039000	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	651000	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	35348000	USD
CY2017	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	820000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-99706000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-42634000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-16960000	USD
CY2019	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	415491000	USD
CY2018	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	485946000	USD
CY2017	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	233889000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt And Capital Securities Net ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet	417262000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt And Capital Securities Net ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet	401965000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt And Capital Securities Net ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet	243553000	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	12018000	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1412000	USD
CY2017	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1319000	USD
CY2019	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	0	USD
CY2018	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	1737000	USD
CY2017	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	0	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	100000000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	75000000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	100000000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	11751000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	13520000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	18555000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	29674000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	24477000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	21672000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6893000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	8871000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3495000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-135063000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-181958000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-98267000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-1727000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-4947000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3452000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-27983000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-43806000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	29712000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	148884000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	192690000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	162978000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	120901000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	148884000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	192690000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	12310000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	15570000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	11504000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	66038000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	49842000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	72578000	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	120732000	USD
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	146185000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	189975000	USD
CY2019Q3	us-gaap	Restricted Cash RestrictedCash	169000	USD
CY2018Q3	us-gaap	Restricted Cash RestrictedCash	2699000	USD
CY2017Q4	us-gaap	Restricted Cash RestrictedCash	2715000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	120901000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	148884000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	192690000	USD
CY2019	us-gaap	Nature Of Operations NatureOfOperations	Description of Business <div style="line-height:120%;padding-bottom:8px;padding-top:8px;text-align:justify;text-indent:48px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">We are a leading global provider of consulting and engineering services that focuses on water, environment, infrastructure, resource management, energy, and international development. We are a global company that leads with science and is renowned for our expertise in providing water-related services for public and private clients. We typically begin at the earliest stage of a project by identifying technical solutions and developing execution plans tailored to our clients' needs and resources. Our solutions may span the entire life cycle of consulting and engineering projects and include applied science, data analysis, research, engineering, design, construction management, and operations and maintenance.</span></div><div style="line-height:120%;padding-bottom:8px;padding-top:8px;text-align:justify;text-indent:48px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Beginning in fiscal 2018, we aligned our operations to better serve our clients and markets, resulting in </span><span style="font-family:inherit;font-size:10pt;"><span>two</span></span><span style="font-family:inherit;font-size:10pt;"> renamed reportable segments. Our Government Services Group (“GSG”) reportable segment primarily includes activities with U.S. government clients (federal, state and local) and activities with development agencies worldwide. Our Commercial/International Services Group (“CIG”) reportable segment primarily includes activities with U.S. commercial clients and international activities other than work for development agencies. This alignment allows us to capitalize on our growing market opportunities and enhance the development of high-end consulting and technical solutions to meet our growing client demand. We continue to report the results of the wind-down of our non-core construction activities in the Remediation and Construction Management (“RCM”) reportable segment. Certain reclassifications were made to the prior years to conform to the current-year presentation.</span></div>
CY2018	ttek	Number Of Renamed Reportable Segments NumberOfRenamedReportableSegments	2	segment
CY2019	us-gaap	Fiscal Period FiscalPeriod	<div style="line-height:120%;padding-bottom:8px;padding-top:8px;text-align:justify;text-indent:48px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;">Fiscal Year.</span><span style="font-family:inherit;font-size:10pt;"> We report results of operations based on 52 or 53-week periods ending on the Sunday nearest September 30. Fiscal years </span><span style="font-family:inherit;font-size:10pt;">2019</span><span style="font-family:inherit;font-size:10pt;">, </span><span style="font-family:inherit;font-size:10pt;">2018</span><span style="font-family:inherit;font-size:10pt;"> and </span><span style="font-family:inherit;font-size:10pt;">2017</span><span style="font-family:inherit;font-size:10pt;"> each contained 52 weeks.</span></div>
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;padding-bottom:8px;padding-top:8px;text-align:justify;text-indent:48px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;">Use of Estimates.</span><span style="font-family:inherit;font-size:10pt;"> The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires us to make estimates and assumptions. These estimates and assumptions affect the amounts reported in our consolidated financial statements and accompanying notes. Although such estimates and assumptions are based on management's best knowledge of current events and actions we may take in the future, actual results could differ materially from those estimates.</span></div>
CY2019	ttek	Maximum Term Of Original Maturity To Classify An Instrument As Cash Equivalent MaximumTermOfOriginalMaturityToClassifyAnInstrumentAsCashEquivalent	P90D
CY2019Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	200000	USD
CY2018Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	2700000	USD
CY2019	ttek	Unbilled Contracts Receivable Period For Billing And Collection UnbilledContractsReceivablePeriodForBillingAndCollection	P12M
CY2019	ttek	Billings In Excess Of Cost Period For Revenue Recognition BillingsInExcessOfCostPeriodForRevenueRecognition	P12M
CY2019	ttek	Number Of Levels Below Reportable Segments For Goodwill Impairment Testing NumberOfLevelsBelowReportableSegmentsForGoodwillImpairmentTesting	1	Level
CY2019	ttek	Concentration Of Credit Risk Number Of Financial Institutions For Investment Exposure ConcentrationOfCreditRiskNumberOfFinancialInstitutionsForInvestmentExposure	1	Institution
CY2019Q3	ttek	Percentage Of Account Receivables Due From Agencies PercentageOfAccountReceivablesDueFromAgencies	0.23
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3107348000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	188762000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16375000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	158668000	USD
CY2019Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	768720000	USD
CY2019Q3	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	114324000	USD
CY2019Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	165611000	USD
CY2019Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	12971000	USD
CY2019Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1071192000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	158761000	USD
CY2019	ttek	Increase Decrease In Accounts Receivable And Contract With Customer Asset IncreaseDecreaseInAccountsReceivableAndContractWithCustomerAsset	10226000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	-6039000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	208513000	USD
CY2019Q3	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	114324000	USD
CY2018Q3	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	142882000	USD
CY2019Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	165611000	USD
CY2018Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	143270000	USD
CY2019Q3	ttek	Contract With Customer Asset Liability Net Current ContractWithCustomerAssetLiabilityNetCurrent	-51287000	USD
CY2018Q3	ttek	Contract With Customer Asset Liability Net Current ContractWithCustomerAssetLiabilityNetCurrent	-388000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	90000000.0	USD
CY2019Q3	us-gaap	Provision For Loss On Contracts ProvisionForLossOnContracts	11500000	USD
CY2018Q3	us-gaap	Provision For Loss On Contracts ProvisionForLossOnContracts	13600000	USD
CY2019Q3	ttek	Revenue Recognition Estimated Cost To Complete Related Contracts RevenueRecognitionEstimatedCostToCompleteRelatedContracts	15200000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3107348000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2964148000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2753360000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3107348000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2964148000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2753360000	USD
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	3100000000	USD
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	1896395000	USD
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	1185076000	USD
CY2019Q3	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	3081471000	USD
CY2018Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	200000000	USD
CY2018Q3	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	25000000	USD
CY2019Q3	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	125000000	USD
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1562521	shares
CY2019	ttek	Shares Repurchased Average Price Per Share SharesRepurchasedAveragePricePerShare	64.00
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	100000000	USD
CY2018Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2018Q4	us-gaap	Dividends Dividends	6654000	USD
CY2019Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2019Q1	us-gaap	Dividends Dividends	6616000	USD
CY2019Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2019Q2	us-gaap	Dividends Dividends	8219000	USD
CY2019Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.15
CY2019Q3	us-gaap	Dividends Dividends	8185000	USD
CY2019	us-gaap	Dividends Dividends	29674000	USD
CY2017Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.10
CY2017Q4	us-gaap	Dividends Dividends	5589000	USD
CY2018Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.10
CY2018Q1	us-gaap	Dividends Dividends	5583000	USD
CY2018Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2018Q2	us-gaap	Dividends Dividends	6664000	USD
CY2018Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2018Q3	us-gaap	Dividends Dividends	6641000	USD
CY2018	us-gaap	Dividends Dividends	24477000	USD
CY2019Q3	us-gaap	Billed Contract Receivables BilledContractReceivables	522256000	USD
CY2018Q3	us-gaap	Billed Contract Receivables BilledContractReceivables	464062000	USD
CY2019Q3	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	300035000	USD
CY2018Q3	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	267739000	USD
CY2019Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	822291000	USD
CY2018Q3	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	731801000	USD
CY2019Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	53571000	USD
CY2018Q3	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	37580000	USD
CY2019Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	768720000	USD
CY2018Q3	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	694221000	USD
CY2019	ttek	Unbilled Contracts Receivable Period For Billing And Collection UnbilledContractsReceivablePeriodForBillingAndCollection	P12M
CY2019Q3	ttek	Government Contract Receivable Unbilled Amounts Related To Claims And Requests For Equitable Adjustment On Contract GovernmentContractReceivableUnbilledAmountsRelatedToClaimsAndRequestsForEquitableAdjustmentOnContract	15000000	USD
CY2018Q3	ttek	Government Contract Receivable Unbilled Amounts Related To Claims And Requests For Equitable Adjustment On Contract GovernmentContractReceivableUnbilledAmountsRelatedToClaimsAndRequestsForEquitableAdjustmentOnContract	74000000	USD
CY2019Q3	ttek	Government Contract Receivable Billed Amounts GovernmentContractReceivableBilledAmounts	129300000	USD
CY2018Q3	ttek	Government Contract Receivable Billed Amounts GovernmentContractReceivableBilledAmounts	89300000	USD
CY2019	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	1100000	USD
CY2018	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-4300000	USD
CY2019Q3	us-gaap	Business Combination Contingent Consideration Arrangements Range Of Outcomes Value High BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh	72400000	USD
CY2019Q3	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	53000000.0	USD
CY2018Q3	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	35290000	USD
CY2017Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	2438000	USD
CY2016Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	8757000	USD
CY2017	ttek	Increase Decrease In Fair Value Of Contingent Consideration Reported In Interest Expense IncreaseDecreaseInFairValueOfContingentConsiderationReportedInInterestExpense	260000	USD
CY2018	ttek	Business Acquisition Contingent Consideration Actual Cash Payment Reported As Cash Flows From Operating Activities BusinessAcquisitionContingentConsiderationActualCashPaymentReportedAsCashFlowsFromOperatingActivities	-2349000	USD
CY2017	ttek	Business Acquisition Contingent Consideration Actual Cash Payment Reported As Cash Flows From Operating Activities BusinessAcquisitionContingentConsiderationActualCashPaymentReportedAsCashFlowsFromOperatingActivities	0	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	12018000	USD
CY2019	ttek	Estimated Earn Out Liabilities For Acquisitions During The Period EstimatedEarnOutLiabilitiesForAcquisitionsDuringThePeriod	27704000	USD
CY2018	ttek	Estimated Earn Out Liabilities For Acquisitions During The Period EstimatedEarnOutLiabilitiesForAcquisitionsDuringThePeriod	32210000	USD
CY2017	ttek	Estimated Earn Out Liabilities For Acquisitions During The Period EstimatedEarnOutLiabilitiesForAcquisitionsDuringThePeriod	1604000	USD
CY2019	ttek	Increase Decrease In Fair Value Of Contingent Consideration Reported In Interest Expense IncreaseDecreaseInFairValueOfContingentConsiderationReportedInInterestExpense	1489000	USD
CY2018	ttek	Increase Decrease In Fair Value Of Contingent Consideration Reported In Interest Expense IncreaseDecreaseInFairValueOfContingentConsiderationReportedInInterestExpense	1005000	USD
CY2019	ttek	Increase Decrease In Fair Value Of Contingent Consideration Reported In Operating Income IncreaseDecreaseInFairValueOfContingentConsiderationReportedInOperatingIncome	1085000	USD
CY2018	ttek	Increase Decrease In Fair Value Of Contingent Consideration Reported In Operating Income IncreaseDecreaseInFairValueOfContingentConsiderationReportedInOperatingIncome	4252000	USD
CY2017	ttek	Increase Decrease In Fair Value Of Contingent Consideration Reported In Operating Income IncreaseDecreaseInFairValueOfContingentConsiderationReportedInOperatingIncome	-6923000	USD
CY2019	ttek	Foreign Currency Transaction And Translation Adjustment ForeignCurrencyTransactionAndTranslationAdjustment	-558000	USD
CY2018	ttek	Foreign Currency Transaction And Translation Adjustment ForeignCurrencyTransactionAndTranslationAdjustment	-854000	USD
CY2017	ttek	Foreign Currency Transaction And Translation Adjustment ForeignCurrencyTransactionAndTranslationAdjustment	59000	USD
CY2019	ttek	Business Acquisition Contingent Consideration Actual Cash Payment Reported As Cash Flows From Operating Activities BusinessAcquisitionContingentConsiderationActualCashPaymentReportedAsCashFlowsFromOperatingActivities	0	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1412000	USD
CY2017	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1319000	USD
CY2019Q3	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	52992000	USD
CY2018Q3	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	35290000	USD
CY2017Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	2438000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	740886000	USD
CY2018	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	85879000	USD
CY2018	us-gaap	Goodwill Written Off Related To Sale Of Business Unit GoodwillWrittenOffRelatedToSaleOfBusinessUnit	12160000	USD
CY2018	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-15785000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	798820000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	146699000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	7755000	USD
CY2019	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-12944000	USD
CY2019Q3	us-gaap	Goodwill Goodwill	924820000	USD
CY2019Q3	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019Q3	us-gaap	Reporting Unit Percentage Of Fair Value In Excess Of Carrying Amount ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount	0.25
CY2019Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	96722000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	80282000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	86237000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	70114000	USD
CY2019	us-gaap	Finite Lived Intangible Assets Foreign Currency Translation Gain Loss FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss	-300000	USD
CY2018	us-gaap	Finite Lived Intangible Assets Foreign Currency Translation Gain Loss FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss	-900000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	11600000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	18200000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	22800000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	9401000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	4551000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	1602000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	886000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	16440000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	149904000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	163364000	USD
CY2019Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	110463000	USD
CY2018Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	120086000	USD
CY2019Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	39441000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	43278000	USD
CY2019	us-gaap	Depreciation Depreciation	17300000	USD
CY2018	us-gaap	Depreciation Depreciation	19600000	USD
CY2017	us-gaap	Depreciation Depreciation	22200000	USD
CY2019Q3	us-gaap	Assets Held For Sale Not Part Of Disposal Group AssetsHeldForSaleNotPartOfDisposalGroup	5400000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	185535000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	180034000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	166074000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-10399000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-5472000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	5687000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	175136000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	174562000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	171761000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	30051000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	46840000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	45604000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	8923000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	9228000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	8860000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	15016000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	10897000	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	9337000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	53990000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	66965000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	63801000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-9108000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-22072000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-4251000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1195000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1471000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-945000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-27312000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-5817000	USD
CY2017	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-4761000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-37615000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-29360000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-9957000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	16375000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	37605000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	53844000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.245
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.034
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.042
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2017	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.034
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.047
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.014
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.018
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Deductions Qualified Production Activities EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Deductions Qualified Production Activities EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities	0.002
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Deductions Qualified Production Activities EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities	0.007
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.010
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.005
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.017
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.020
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.029
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0.009
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0.017
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2019	ttek	Effective Income Tax Rate Reconciliation Sharebased Payment Arrangement Percent EffectiveIncomeTaxRateReconciliationSharebasedPaymentArrangementPercent	-0.024
CY2018	ttek	Effective Income Tax Rate Reconciliation Sharebased Payment Arrangement Percent EffectiveIncomeTaxRateReconciliationSharebasedPaymentArrangementPercent	-0.027
CY2017	ttek	Effective Income Tax Rate Reconciliation Sharebased Payment Arrangement Percent EffectiveIncomeTaxRateReconciliationSharebasedPaymentArrangementPercent	-0.028
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.135
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.005
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.005
CY2019	ttek	Effective Income Tax Rate Reconciliation Change In Uncertain Tax Positions Percent EffectiveIncomeTaxRateReconciliationChangeInUncertainTaxPositionsPercent	0.024
CY2018	ttek	Effective Income Tax Rate Reconciliation Change In Uncertain Tax Positions Percent EffectiveIncomeTaxRateReconciliationChangeInUncertainTaxPositionsPercent	0.019
CY2017	ttek	Effective Income Tax Rate Reconciliation Change In Uncertain Tax Positions Percent EffectiveIncomeTaxRateReconciliationChangeInUncertainTaxPositionsPercent	0.018
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Percent	-0.014
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Percent	-0.084
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Percent	0
CY2019	ttek	Effective Income Tax Rate Reconciliation Other Non Recurring Adjustments To Deferred Taxes Percent EffectiveIncomeTaxRateReconciliationOtherNonRecurringAdjustmentsToDeferredTaxesPercent	-0.004
CY2018	ttek	Effective Income Tax Rate Reconciliation Other Non Recurring Adjustments To Deferred Taxes Percent EffectiveIncomeTaxRateReconciliationOtherNonRecurringAdjustmentsToDeferredTaxesPercent	0.021
CY2017	ttek	Effective Income Tax Rate Reconciliation Other Non Recurring Adjustments To Deferred Taxes Percent EffectiveIncomeTaxRateReconciliationOtherNonRecurringAdjustmentsToDeferredTaxesPercent	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Transition Tax On Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017TransitionTaxOnAccumulatedForeignEarningsPercent	0.014
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Transition Tax On Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017TransitionTaxOnAccumulatedForeignEarningsPercent	0
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Transition Tax On Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017TransitionTaxOnAccumulatedForeignEarningsPercent	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.033
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.018
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.002
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.093
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.215
CY2017	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.313
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.093
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.215
CY2017	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.313
CY2019	ttek	Tax Cuts And Jobs Act Transition Tax For Accumulated Foreign Earnings Income Tax Expense TaxCutsAndJobsActTransitionTaxForAccumulatedForeignEarningsIncomeTaxExpense	2400000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.245
CY2018	ttek	Tax Cuts And Jobs Act Change In Tax Rate Income Tax Expense Benefit TaxCutsAndJobsActChangeInTaxRateIncomeTaxExpenseBenefit	-10100000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.245
CY2018Q4	ttek	Tax Cuts And Jobs Act Change In Tax Rate Income Tax Expense Benefit TaxCutsAndJobsActChangeInTaxRateIncomeTaxExpenseBenefit	-2600000	USD
CY2019	ttek	Effective Income Tax Rate Reconciliation Excluding Sharebased Compensation Excess Tax Benefit And Tax Cuts And Jobs Act Impacts Percent EffectiveIncomeTaxRateReconciliationExcludingSharebasedCompensationExcessTaxBenefitAndTaxCutsAndJobsActImpactsPercent	0.219
CY2018	ttek	Effective Income Tax Rate Reconciliation Excluding Sharebased Compensation Excess Tax Benefit And Tax Cuts And Jobs Act Impacts Percent EffectiveIncomeTaxRateReconciliationExcludingSharebasedCompensationExcessTaxBenefitAndTaxCutsAndJobsActImpactsPercent	0.251
CY2019	ttek	Tax Cuts And Jobs Act Gilti Provision TaxCutsAndJobsActGILTIProvision	400000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	764000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	1220000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	5500000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	2646000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	7506000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	4259000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	28232000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	19611000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	6700000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	6338000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	39782000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	23492000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	20543000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	21479000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	67941000	USD
CY2018Q3	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	36087000	USD
CY2019Q3	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	21886000	USD
CY2018Q3	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	25819000	USD
CY2019Q3	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	3026000	USD
CY2018Q3	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	3524000	USD
CY2019Q3	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	26482000	USD
CY2018Q3	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	23319000	USD
CY2019Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1133000	USD
CY2018Q3	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4984000	USD
CY2019Q3	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	52527000	USD
CY2018Q3	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	57646000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	15414000	USD
CY2018Q3	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	21559000	USD
CY2019Q3	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	44000000.0	USD
CY2019	ttek	Foreign Earnings Repatriated Tax Expense Benefit ForeignEarningsRepatriatedTaxExpenseBenefit	1100000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	20500000	USD
CY2019Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9200000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	8328000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9337000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	22786000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1342000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1928000	USD
CY2017Q1	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1060000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	356000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1116000	USD
CY2017Q1	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	2365000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	100000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2017Q1	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	6875000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	757000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	4053000	USD
CY2017Q1	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	9999000	USD
CY2019Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9169000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	8328000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	9337000	USD
CY2019	ttek	Unrecognized Tax Benefits Accrued Interest Expense From Settlements With Taxing Authorities UnrecognizedTaxBenefitsAccruedInterestExpenseFromSettlementsWithTaxingAuthorities	500000	USD
CY2018	ttek	Unrecognized Tax Benefits Accrued Interest Expense From Settlements With Taxing Authorities UnrecognizedTaxBenefitsAccruedInterestExpenseFromSettlementsWithTaxingAuthorities	600000	USD
CY2017	ttek	Unrecognized Tax Benefits Accrued Interest Expense From Settlements With Taxing Authorities UnrecognizedTaxBenefitsAccruedInterestExpenseFromSettlementsWithTaxingAuthorities	400000	USD
CY2019	us-gaap	Tax Adjustments Settlements And Unusual Provisions TaxAdjustmentsSettlementsAndUnusualProvisions	200000	USD
CY2018	us-gaap	Tax Adjustments Settlements And Unusual Provisions TaxAdjustmentsSettlementsAndUnusualProvisions	300000	USD
CY2017	us-gaap	Tax Adjustments Settlements And Unusual Provisions TaxAdjustmentsSettlementsAndUnusualProvisions	900000	USD
CY2019Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	2400000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1200000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1100000	USD
CY2019Q3	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	276521000	USD
CY2018Q3	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	277311000	USD
CY2019Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	12572000	USD
CY2018Q3	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	12599000	USD
CY2019Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	263949000	USD
CY2018Q3	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	264712000	USD
CY2019Q3	us-gaap	Line Of Credit LineOfCredit	276400000	USD
CY2019Q3	ttek	Long Term Debt Weighted Average Interest Rate Including Effects Of Interest Rate Swap LongTermDebtWeightedAverageInterestRateIncludingEffectsOfInterestRateSwap	0.0365
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	12572000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	12515000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	15625000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	235809000	USD
CY2019Q3	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	276521000	USD
CY2019	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	79300000	USD
CY2018	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	77800000	USD
CY2017Q1	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	71300000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	108758000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due Current CapitalLeasesFutureMinimumPaymentsDueCurrent	72000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	66418000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due In Two Years CapitalLeasesFutureMinimumPaymentsDueInTwoYears	15000	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	51424000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due In Three Years CapitalLeasesFutureMinimumPaymentsDueInThreeYears	0	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	36463000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due In Four Years CapitalLeasesFutureMinimumPaymentsDueInFourYears	0	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	25777000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due In Five Years CapitalLeasesFutureMinimumPaymentsDueInFiveYears	0	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	54692000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due Thereafter CapitalLeasesFutureMinimumPaymentsDueThereafter	0	USD
CY2019Q3	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	343532000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Due CapitalLeasesFutureMinimumPaymentsDue	87000	USD
CY2019Q3	us-gaap	Capital Leases Future Minimum Payments Present Value Of Net Minimum Payments CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments	87000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	17618000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	19582000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13450000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4016000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5288000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4715000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	13602000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	14294000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	8735000	USD
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1355000	shares
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	30.87
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	456000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	26.21
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	5000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	23.48
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	894000	shares
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	33.28
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P5Y29D
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	46176000	USD
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	894000	shares
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice	33.28
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1	P5Y29D
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue	46176000	USD
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	671000	shares
CY2019Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	30.75
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P4Y3M29D
CY2019Q3	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	36346000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0	shares
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	23300000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	22400000	USD
CY2017	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	11400000	USD
CY2019Q3	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	30400000	USD
CY2018Q3	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	29400000	USD
CY2019Q3	us-gaap	Deferred Compensation Liability Classified Noncurrent DeferredCompensationLiabilityClassifiedNoncurrent	29500000	USD
CY2018Q3	us-gaap	Deferred Compensation Liability Classified Noncurrent DeferredCompensationLiabilityClassifiedNoncurrent	30200000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	158668000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	136883000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	117874000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54986000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55670000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	56911000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	950000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	928000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1002000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55936000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56598000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	57913000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.89
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.46
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.07
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.84
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.42
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.04
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	100000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-28441000	USD
CY2018	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	409000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-28850000	USD
CY2019	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-32356000	USD
CY2019	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	878000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-33234000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	28802000	USD
CY2017Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
CY2019Q3	us-gaap	Line Of Credit LineOfCredit	276400000	USD
CY2019Q3	ttek	Loss Contingency Number Of Actions LossContingencyNumberOfActions	3	action
CY2019	ttek	Number Of Renamed Reportable Segments NumberOfRenamedReportableSegments	2	segment
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3107348000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2964148000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2753360000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	188762000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	190086000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	183342000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	11600000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	18200000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	22800000	USD
CY2019	ttek	Fair Value Adjustments To Contingent Consideration FairValueAdjustmentsToContingentConsideration	-1100000	USD
CY2018	ttek	Fair Value Adjustments To Contingent Consideration FairValueAdjustmentsToContingentConsideration	-4300000	USD
CY2017	ttek	Fair Value Adjustments To Contingent Consideration FairValueAdjustmentsToContingentConsideration	6900000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	7800000	USD
CY2019Q3	us-gaap	Assets Assets	2147408000	USD
CY2018Q3	us-gaap	Assets Assets	1959421000	USD
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.51
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.60
CY2019	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	99100000	USD
CY2018	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	75000000.0	USD
CY2017	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	56100000	USD
CY2019	us-gaap	Related Party Transaction Expenses From Transactions With Related Party RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty	98500000	USD
CY2018	us-gaap	Related Party Transaction Expenses From Transactions With Related Party RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty	76600000	USD
CY2017	us-gaap	Related Party Transaction Expenses From Transactions With Related Party RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty	53900000	USD
CY2019Q3	us-gaap	Accounts Receivable Related Parties AccountsReceivableRelatedParties	19351000	USD
CY2018Q3	us-gaap	Accounts Receivable Related Parties AccountsReceivableRelatedParties	20279000	USD
CY2019Q3	ttek	Contract With Customer Asset Related Party ContractWithCustomerAssetRelatedParty	9681000	USD
CY2018Q3	ttek	Contract With Customer Asset Related Party ContractWithCustomerAssetRelatedParty	10584000	USD
CY2019Q3	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	111000	USD
CY2018Q3	us-gaap	Due To Related Parties Current And Noncurrent DueToRelatedPartiesCurrentAndNoncurrent	193000	USD
CY2017Q4	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Change In Tax Rate Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpenseBenefit	-14700000	USD
CY2018Q3	ttek	Decrease In Revenue Related To Construction Settlement DecreaseInRevenueRelatedToConstructionSettlement	10600000	USD
CY2018Q3	us-gaap	Loss On Contract Termination LossOnContractTermination	12500000	USD
CY2019Q1	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-23400000	USD
CY2019Q3	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	7800000	USD
CY2019Q3	us-gaap	Restructuring Charges RestructuringCharges	10900000	USD
CY2018Q4	us-gaap	Revenues Revenues	717431000	USD
CY2019Q1	us-gaap	Revenues Revenues	722621000	USD
CY2019Q2	us-gaap	Revenues Revenues	825793000	USD
CY2019Q3	us-gaap	Revenues Revenues	841502000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	55711000	USD
CY2019Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	47545000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	64841000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	20665000	USD
CY2018Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	41997000	USD
CY2019Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	55911000	USD
CY2019Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	49233000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	11527000	USD
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.01
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.90
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.21
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.00
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.88
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.21
CY2018Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55390000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55143000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54819000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54617000	shares
CY2018Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56366000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55985000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55768000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55618000	shares
CY2017Q4	us-gaap	Revenues Revenues	759749000	USD
CY2018Q2	us-gaap	Revenues Revenues	700262000	USD
CY2018Q3	us-gaap	Revenues Revenues	764795000	USD
CY2018Q3	us-gaap	Revenues Revenues	739343000	USD
CY2017Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	48589000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	42716000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	55496000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	43285000	USD
CY2017Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	46034000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	28725000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	33322000	USD
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.52
CY2017Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.81
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.59
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2017Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55855000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55841000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55537000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55341000	shares
CY2017Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56875000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56673000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56390000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56349000	shares

Files In Submission

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$TTEK
TETRA TECH INC Stock $ttek

2019 Q3 Form 10-K Financial Statement

#000083164119000193 Filed on November 29, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$TTEK TETRA TECH INC Stock $ttek

2019 Q3 Form 10-K Financial Statement

#000083164119000193 Filed on November 29, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$TTEK
TETRA TECH INC Stock $ttek