v3.25.4
Since Inception [Member] Expense Example - Putnam Retirement Advantage 2040 Fund
Aug. 31, 2025
USD ($)
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 1,190
Expense Example, with Redemption, 10 Years 2,241
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 1,049
Expense Example, with Redemption, 10 Years 2,382
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 866
Expense Example, with Redemption, 10 Years 2,208
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 735
Expense Example, with Redemption, 10 Years 1,939
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 603
Expense Example, with Redemption, 10 Years 1,665
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 520
Expense Example, with Redemption, 10 Years 1,495
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 466
Expense Example, with Redemption, 10 Years 1,380
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 520
Expense Example, with Redemption, 10 Years $ 1,495