S000003876 [Member] Expense Example, No Redemption - Putnam VT Income Fund |
Dec. 31, 2025
USD ($)
|
|---|---|
| Class IA Shares | |
| Prospectus [Line Items] | |
| Expense Example, No Redemption, 1 Year | $ 58 |
| Expense Example, No Redemption, 3 Years | 183 |
| Expense Example, No Redemption, 5 Years | 318 |
| Expense Example, No Redemption, 10 Years | 713 |
| Class IB Shares | |
| Prospectus [Line Items] | |
| Expense Example, No Redemption, 1 Year | 84 |
| Expense Example, No Redemption, 3 Years | 262 |
| Expense Example, No Redemption, 5 Years | 456 |
| Expense Example, No Redemption, 10 Years | $ 1,015 |