v3.25.2
Equity - Schedule of shares outstanding (Details) - JPY (¥)
¥ in Millions
12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Changes in number of shares outstanding [abstract]    
Number of shares issued 122,587,617 122,587,617
Number of shares outstanding at beginning of period (in shares) 122,587,617 122,587,617
Issued capital, ordinary shares [1] ¥ 196 ¥ 196
Issuance of new shares ¥ 1,077  
Number of shares issued 130,814,526 122,587,617
Number of shares outstanding at end of period (in shares) 130,814,526 122,587,617
Issued capital, ordinary shares ¥ 213 ¥ 196 [1]
Issuance of shares in Reverse Recapitalization    
Changes in number of shares outstanding [abstract]    
Increase (decrease) in number of shares outstanding 7,115,459 0
Increase (decrease) in number of ordinary shares issued 7,115,459 0
Issuance of new shares ¥ 15 ¥ 0
Issuance of shares in business acquisition    
Changes in number of shares outstanding [abstract]    
Increase (decrease) in number of shares outstanding 1,111,450 0
Increase (decrease) in number of ordinary shares issued 1,111,450 0
Issuance of new shares ¥ 2 ¥ 0
[1] The comparative information is restated due to change in accounting policy. See Note 2 (5) “Changes in