v3.26.1
Deferred taxes and incomes tax expenses (benefits) - Total deferred tax assets and liabilities (Details) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets ¥ 337  
Deferred tax liabilities [1] 79  
Deferred tax assets 378 ¥ 337
Deferred tax liabilities [1] 562 79
Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 836 857
Recognized through profit or loss (95) (20)
Recognized in OCI (1)  
Addition (business combination) 53 0
Deferred tax assets 793 836
Deferred tax liabilities    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax liabilities 578 505
Recognized through profit or loss (145) (6)
Recognized in OCI 22  
Addition (business combination) 523 79
Deferred tax liabilities 977 578
Lease liabilities | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 425 522
Recognized through profit or loss (133) (97)
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 292 425
Tax losses carried forward(1) | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 0 26
Recognized through profit or loss (16) (26)
Recognized in OCI (1)  
Addition (business combination) 53 0
Deferred tax assets 36 0
Accrued enterprise tax | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 49 36
Recognized through profit or loss (12) 13
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 37 49
Accrued bonuses | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 98 71
Recognized through profit or loss (32) 27
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 66 98
Accrued expenses | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 76 98
Recognized through profit or loss (58) (22)
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 18 76
Accrued paid leaves | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 16 16
Recognized through profit or loss 8 0
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 24 16
Leasehold improvements | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 36 19
Recognized through profit or loss 28 17
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 65 36
Asset retirement obligations | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 107 37
Recognized through profit or loss (2) 70
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax assets 104 107
Other | Deferred tax assets    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax assets 29 33
Recognized through profit or loss 122 (4)
Recognized in OCI 0  
Addition (business combination) 0
Deferred tax assets 151 29
Other | Deferred tax liabilities    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax liabilities 0  
Recognized through profit or loss 1  
Recognized in OCI 0  
Addition (business combination) 0  
Deferred tax liabilities 1 0
Lease assets | Deferred tax liabilities    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax liabilities 395 499
Recognized through profit or loss (106) (104)
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax liabilities 290 395
Asset retirement obligation | Deferred tax liabilities    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax liabilities 104 6
Recognized through profit or loss (16) 98
Recognized in OCI 0  
Addition (business combination) 0 0
Deferred tax liabilities 87 104
Identifiable intangible assets | Deferred tax liabilities    
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]    
Deferred tax liabilities 79 0
Recognized through profit or loss (24) 0
Recognized in OCI 22  
Addition (business combination) 523 79
Deferred tax liabilities ¥ 600 ¥ 79
[1] Revised based on adjustments to the original provisional amounts made in March 2025 for Next Finance Tech’s identifiable assets acquired and liabilities assumed. Next Finance Tech was acquired by the Company in March 2025.