v3.25.4
Expense Example
Sep. 30, 2025
USD ($)
MSIFT Discovery Portfolio - Classes I, A, L, C and R6 | Discovery Portfolio | Class I  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 77
Expense Example, with Redemption, 3 Years 240
Expense Example, with Redemption, 5 Years 417
Expense Example, with Redemption, 10 Years 930
MSIFT Discovery Portfolio - Classes I, A, L, C and R6 | Discovery Portfolio | Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 625
Expense Example, with Redemption, 3 Years 836
Expense Example, with Redemption, 5 Years 1,064
Expense Example, with Redemption, 10 Years 1,718
MSIFT Discovery Portfolio - Classes I, A, L, C and R6 | Discovery Portfolio | Class L  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 159
Expense Example, with Redemption, 3 Years 493
Expense Example, with Redemption, 5 Years 850
Expense Example, with Redemption, 10 Years 1,856
MSIFT Discovery Portfolio - Classes I, A, L, C and R6 | Discovery Portfolio | Class C  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 281
Expense Example, with Redemption, 3 Years 560
Expense Example, with Redemption, 5 Years 964
Expense Example, with Redemption, 10 Years 1,897
MSIFT Discovery Portfolio - Classes I, A, L, C and R6 | Discovery Portfolio | Class R6  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 64
Expense Example, with Redemption, 3 Years 202
Expense Example, with Redemption, 5 Years 351
Expense Example, with Redemption, 10 Years 786
MSIFT Corporate Bond Portfolio - Classes I, A, L, and C | Corporate Bond Portfolio | Class I  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 66
Expense Example, with Redemption, 3 Years 268
Expense Example, with Redemption, 5 Years 487
Expense Example, with Redemption, 10 Years 1,117
MSIFT Corporate Bond Portfolio - Classes I, A, L, and C | Corporate Bond Portfolio | Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 424
Expense Example, with Redemption, 3 Years 664
Expense Example, with Redemption, 5 Years 923
Expense Example, with Redemption, 10 Years 1,664
MSIFT Corporate Bond Portfolio - Classes I, A, L, and C | Corporate Bond Portfolio | Class L  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 150
Expense Example, with Redemption, 3 Years 507
Expense Example, with Redemption, 5 Years 889
Expense Example, with Redemption, 10 Years 1,959
MSIFT Corporate Bond Portfolio - Classes I, A, L, and C | Corporate Bond Portfolio | Class C  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 278
Expense Example, with Redemption, 3 Years 620
Expense Example, with Redemption, 5 Years 1,088
Expense Example, with Redemption, 10 Years 2,145
MSIFT Ultra-Short Portfolios - Classes IR, Institutional Class, Class A | Ultra-Short Income Portfolio | Class IR  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 26
Expense Example, with Redemption, 3 Years 91
Expense Example, with Redemption, 5 Years 164
Expense Example, with Redemption, 10 Years 376
MSIFT Ultra-Short Portfolios - Classes IR, Institutional Class, Class A | Ultra-Short Income Portfolio | Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 31
Expense Example, with Redemption, 3 Years 107
Expense Example, with Redemption, 5 Years 191
Expense Example, with Redemption, 10 Years 438
MSIFT Ultra-Short Portfolios - Classes IR, Institutional Class, Class A | Ultra-Short Income Portfolio | Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 41
Expense Example, with Redemption, 3 Years 161
Expense Example, with Redemption, 5 Years 292
Expense Example, with Redemption, 10 Years 675
MSIFT Global Strategist Portfolio - Classes I, A, L, C and R6 | Global Strategist Portfolio | Class I  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 76
Expense Example, with Redemption, 3 Years 256
Expense Example, with Redemption, 5 Years 452
Expense Example, with Redemption, 10 Years 1,017
MSIFT Global Strategist Portfolio - Classes I, A, L, C and R6 | Global Strategist Portfolio | Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 626
Expense Example, with Redemption, 3 Years 842
Expense Example, with Redemption, 5 Years 1,074
Expense Example, with Redemption, 10 Years 1,740
MSIFT Global Strategist Portfolio - Classes I, A, L, C and R6 | Global Strategist Portfolio | Class L  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 161
Expense Example, with Redemption, 3 Years 499
Expense Example, with Redemption, 5 Years 860
Expense Example, with Redemption, 10 Years 1,878
MSIFT Global Strategist Portfolio - Classes I, A, L, C and R6 | Global Strategist Portfolio | Class C  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 287
Expense Example, with Redemption, 3 Years 654
Expense Example, with Redemption, 5 Years 1,147
Expense Example, with Redemption, 10 Years 2,213
MSIFT Global Strategist Portfolio - Classes I, A, L, C and R6 | Global Strategist Portfolio | Class R6  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 69
Expense Example, with Redemption, 3 Years 218
Expense Example, with Redemption, 5 Years 379
Expense Example, with Redemption, 10 Years $ 847