v3.25.4
Since Inception [Member] Expense Example - Putnam Retirement Advantage 2045 Fund
Aug. 31, 2025
USD ($)
Class C  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 258
Expense Example, with Redemption, 3 Years 490
Expense Example, with Redemption, 5 Years 1,095
Expense Example, with Redemption, 10 Years 2,548
Class R  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 122
Expense Example, with Redemption, 3 Years 381
Expense Example, with Redemption, 5 Years 914
Expense Example, with Redemption, 10 Years 2,376
Class R3  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 97
Expense Example, with Redemption, 3 Years 303
Expense Example, with Redemption, 5 Years 784
Expense Example, with Redemption, 10 Years 2,113
Class R4  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 72
Expense Example, with Redemption, 3 Years 225
Expense Example, with Redemption, 5 Years 651
Expense Example, with Redemption, 10 Years 1,840
Class R5  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 56
Expense Example, with Redemption, 3 Years 176
Expense Example, with Redemption, 5 Years 569
Expense Example, with Redemption, 10 Years 1,673
Class R6  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 46
Expense Example, with Redemption, 3 Years 144
Expense Example, with Redemption, 5 Years 515
Expense Example, with Redemption, 10 Years 1,560
Class Y  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 56
Expense Example, with Redemption, 3 Years 176
Expense Example, with Redemption, 5 Years 569
Expense Example, with Redemption, 10 Years 1,673
Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 652
Expense Example, with Redemption, 3 Years 816
Expense Example, with Redemption, 5 Years 1,238
Expense Example, with Redemption, 10 Years $ 2,413