Label	Element	Value
Prospectus [Line Items]	rr_ProspectusLineItems
Document Type	dei_DocumentType	485BPOS
Document Period End Date	dei_DocumentPeriodEndDate	Dec. 31, 2018
Entity Registrant Name	dei_EntityRegistrantName	PUTNAM FUNDS TRUST
Entity Central Index Key	dei_EntityCentralIndexKey	0001005942
Amendment Flag	dei_AmendmentFlag	false
Entity Inv Company Type	dei_EntityInvCompanyType	N-1A
Trading Symbol	dei_TradingSymbol	PFT
Document Creation Date	dei_DocumentCreationDate	Jun. 21, 2019
Document Effective Date	dei_DocumentEffectiveDate	Jun. 24, 2019
Prospectus Date	rr_ProspectusDate	Jun. 24, 2019
Putnam Focused Equity Fund
Prospectus [Line Items]	rr_ProspectusLineItems
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
Footnote	PFT_FootnotetText	*Prior to June 24, 2019, the fund was known as Putnam Global Industrials Fund.
Objective [Heading]	rr_ObjectiveHeading	Goal
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Putnam Focused Equity Fund seeks capital appreciation.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 14 of the fund’s prospectus, in the Appendix to the fund’s prospectus, and in How to buy shares beginning on page II-1 of the fund’s statement of additional information (SAI).
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The fund pays transaction-related costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher turnover rate may indicate higher transaction costs and may result in higher taxes when the fund’s shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund’s turnover rate in the most recent fiscal year was 293%.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	293.00%
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Putnam funds. More information about these and other discounts is available from your financial advisor and in How do I buy fund shares? beginning on page 14 of the fund's prospectus, in the Appendix to the fund's prospectus, and in How to buy shares beginning on page II-1 of the fund's statement of additional information (SAI).
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 50,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. It assumes that you invest $10,000 in the fund for the time periods indicated and then, except as indicated, redeem all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund’s operating expenses remain the same. Your actual costs may be higher or lower.
Strategy [Heading]	rr_StrategyHeading	Investments, risks, and performance
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Investments We invest mainly in equity securities (growth or value or both) of large and midsize companies that we believe have favorable investment potential. We may consider, among other factors, a company’s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. Under normal circumstances, we invest at least 80% of the fund’s net assets in equity investments, including common stocks, preferred stocks, convertible securities, warrants, American Depositary Receipts (ADRs) and Global Depositary Receipts (GDRs). This policy may be changed only after 60 days’ notice to shareholders. The fund is “non-diversified,” which means it may invest a greater percentage of its assets in fewer issuers than a “diversified” fund. The fund expects to concentrate its investments in a limited number of issuers.
Risk [Heading]	rr_RiskHeading	Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	It is important to understand that you can lose money by investing in the fund. The value of investments in the fund’s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions, investor sentiment and market perceptions, government actions, geopolitical events or changes, and factors related to a specific issuer, geography, industry or sector. These and other factors may lead to increased volatility and reduced liquidity in the fund’s portfolio holdings. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. These risks are generally greater for small and midsize companies. The fund will be more susceptible to these risks than other funds because it concentrates its investments in a limited number of issuers or sectors, and the fund may perform poorly as a result of adverse developments affecting those issuers or sectors. As a non-diversified fund, the fund invests in fewer issuers and is more vulnerable than a more broadly diversified fund to fluctuations in the values of the securities it holds. The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text]	rr_RiskLoseMoney	It is important to understand that you can lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Nondiversified Status [Text]	rr_RiskNondiversifiedStatus	As a non-diversified fund, the fund invests in fewer issuers and is more vulnerable than a more broadly diversified fund to fluctuations in the values of the securities it holds.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time. Before June 24, 2019, the fund was managed with a materially different investment strategy and may have achieved materially different performance results under its current investment strategy from that shown for periods before this date. The bar chart does not reflect the impact of sales charges. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results. Monthly performance figures for the fund are available at putnam.com.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund’s performance year to year and over time.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	putnam.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Please remember that past performance is not necessarily an indication of future results.
Bar Chart [Heading]	rr_BarChartHeading	Annual total returns for class A shares before sales charges
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart does not reflect the impact of sales charges. If it did, performance would be lower.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Year-to-date performance through 3/31/19  19.34% Best calendar quarter Q2 2009   21.43% Worst calendar quarter Q3 2011 −28.22%
Year to Date Return, Label	rr_YearToDateReturnLabel	Year-to-date performance
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Mar. 31, 2019
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	19.34%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best calendar quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	21.43%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst calendar quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(28.22%)
Performance Table Heading	rr_PerformanceTableHeading	Average annual total returns after sales charges (for periods ended 12/31/18)
Performance Table Market Index Changed	rr_PerformanceTableMarketIndexChanged	As of June 24, 2019, the S&P 500 Index (an unmanaged index of common stock performance) replaced the MSCI World Industrials Index (ND) (a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets in the industrials sector) as the benchmark for this fund because, in Putnam Management’s opinion, the securities tracked by the S&P 500 Index more accurately reflect the types of securities that generally will be held by the fund.
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on an investor's tax situation and may differ from those shown.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for class A shares only and will vary for other classes.
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes. These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an IRA, or another tax-advantaged arrangement. Class B share performance reflects conversion to class A shares after eight years.
Putnam Focused Equity Fund | S&P 500 Index (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(4.38%)	[1]
5 Years	rr_AverageAnnualReturnYear05	8.49%	[1]
10 Years	rr_AverageAnnualReturnYear10	13.12%	[1]
Putnam Focused Equity Fund | MSCI World Industrials (ND)-S&P 500 Linked Benchmark (no deduction for fees, expenses or taxes)
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(14.54%)	[2]
5 Years	rr_AverageAnnualReturnYear05	3.51%	[2]
10 Years	rr_AverageAnnualReturnYear10	10.08%	[2]
Putnam Focused Equity Fund | Class A
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	5.75%
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[3]
Management fees	rr_ManagementFeesOverAssets	0.62%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other expenses	rr_OtherExpensesOverAssets	0.40%	[4]
Total annual fund operating expenses	rr_ExpensesOverAssets	1.27%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 697
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	955
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,232
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 2,021
Annual Return 2009	rr_AnnualReturn2009	24.67%
Annual Return 2010	rr_AnnualReturn2010	32.52%
Annual Return 2011	rr_AnnualReturn2011	(14.67%)
Annual Return 2012	rr_AnnualReturn2012	27.01%
Annual Return 2013	rr_AnnualReturn2013	40.45%
Annual Return 2014	rr_AnnualReturn2014	0.60%
Annual Return 2015	rr_AnnualReturn2015	1.67%
Annual Return 2016	rr_AnnualReturn2016	14.85%
Annual Return 2017	rr_AnnualReturn2017	27.76%
Annual Return 2018	rr_AnnualReturn2018	(13.94%)
1 Year	rr_AverageAnnualReturnYear01	(18.89%)
5 Years	rr_AverageAnnualReturnYear05	4.01%
10 Years	rr_AverageAnnualReturnYear10	11.84%
Putnam Focused Equity Fund | Class A | after taxes on distributions
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(20.44%)
5 Years	rr_AverageAnnualReturnYear05	1.78%
10 Years	rr_AverageAnnualReturnYear10	9.84%
Putnam Focused Equity Fund | Class A | after taxes on distributions and sale of fund shares
Prospectus [Line Items]	rr_ProspectusLineItems
1 Year	rr_AverageAnnualReturnYear01	(10.14%)
5 Years	rr_AverageAnnualReturnYear05	2.46%
10 Years	rr_AverageAnnualReturnYear10	9.13%
Putnam Focused Equity Fund | Class B
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	5.00%	[5]
Management fees	rr_ManagementFeesOverAssets	0.62%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.40%	[4]
Total annual fund operating expenses	rr_ExpensesOverAssets	2.02%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 705
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	934
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,288
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,155
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	205
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	634
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,088
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 2,155
1 Year	rr_AverageAnnualReturnYear01	(18.49%)
5 Years	rr_AverageAnnualReturnYear05	4.18%
10 Years	rr_AverageAnnualReturnYear10	11.85%
Putnam Focused Equity Fund | Class C
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[6]
Management fees	rr_ManagementFeesOverAssets	0.62%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.40%	[4]
Total annual fund operating expenses	rr_ExpensesOverAssets	2.02%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 305
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	634
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,088
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	2,348
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	205
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	634
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	1,088
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 2,348
1 Year	rr_AverageAnnualReturnYear01	(15.34%)
5 Years	rr_AverageAnnualReturnYear05	4.46%
10 Years	rr_AverageAnnualReturnYear10	11.69%
Putnam Focused Equity Fund | Class M
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	3.50%
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.62%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.75%
Other expenses	rr_OtherExpensesOverAssets	0.40%	[4]
Total annual fund operating expenses	rr_ExpensesOverAssets	1.77%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 524
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	888
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,276
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 2,361
1 Year	rr_AverageAnnualReturnYear01	(17.38%)
5 Years	rr_AverageAnnualReturnYear05	3.98%
10 Years	rr_AverageAnnualReturnYear10	11.57%
Putnam Focused Equity Fund | Class R
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.62%
Distribution and service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other expenses	rr_OtherExpensesOverAssets	0.40%	[4]
Total annual fund operating expenses	rr_ExpensesOverAssets	1.52%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 155
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	480
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	829
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,813
1 Year	rr_AverageAnnualReturnYear01	(14.13%)
5 Years	rr_AverageAnnualReturnYear05	5.00%
10 Years	rr_AverageAnnualReturnYear10	12.25%
Putnam Focused Equity Fund | Class R6
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.62%
Other expenses	rr_OtherExpensesOverAssets	0.26%	[7]
Total annual fund operating expenses	rr_ExpensesOverAssets	0.88%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 90
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	281
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	488
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,084
1 Year	rr_AverageAnnualReturnYear01	(13.68%)	[8]
5 Years	rr_AverageAnnualReturnYear05	5.53%	[8]
10 Years	rr_AverageAnnualReturnYear10	12.80%	[8]
Putnam Focused Equity Fund | Class Y
Prospectus [Line Items]	rr_ProspectusLineItems
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)	rr_MaximumDeferredSalesChargeOverOther	none
Management fees	rr_ManagementFeesOverAssets	0.62%
Other expenses	rr_OtherExpensesOverAssets	0.40%	[4]
Total annual fund operating expenses	rr_ExpensesOverAssets	1.02%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 104
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	325
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	536
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,248
1 Year	rr_AverageAnnualReturnYear01	(13.72%)
5 Years	rr_AverageAnnualReturnYear05	5.52%
10 Years	rr_AverageAnnualReturnYear10	12.79%

[1] As of June 24, 2019, the S&P 500 Index (an unmanaged index of common stock performance) replaced the MSCI World Industrials Index (ND) (a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets in the industrials sector) as the benchmark for this fund because, in Putnam Management's opinion, the securities tracked by the S&P 500 Index more accurately reflect the types of securities that generally will be held by the fund. The average annual total returns of the MSCI World Industrials Index (ND) for the one-year, five-year, and ten-year periods ended on December 31, 2018 were -14.54%, 3.51%, and 10.08%, respectively.

[2] The MSCI World Industrials (ND)-S&P 500 Linked Benchmark represents performance of the MSCI World Industrials Index (ND) from the inception date of the fund, December 18, 2018, through June 23, 2019 and performance of the S&P 500 Index from June 24, 2019 forward.

[3] Applies only to certain redemptions of shares originally purchased with no initial sales charge.

[4] Restated to reflect current fees.

[5] This charge is phased out over six years.

[6] This charge is eliminated after one year.

[7] Other expenses are based on expenses of class A shares for the fund's last fiscal year, restated to reflect current fees, and restated to reflect the lower investor servicing fees applicable to class R6 shares.

[8] Performance for class R6 shares prior to their inception (5/22/18) is derived from the historical performance of class Y shares and has not been adjusted for the lower investor servicing fees applicable to class R6 shares; had it, returns would have been higher.