v3.26.1
Property, Plant and Equipment - Schedule of Reconciliation of Changes in Right-of-use Assets (Details) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance ¥ 481,492 ¥ 533,403
Ending balance 483,120 481,492
Acquisition cost of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 740,204 763,989
Additions and other increases 25,882 24,986
Disposals and other decreases (20,854) (37,286)
Foreign currency translation differences 51,552 (11,484)
Ending balance 796,785 740,204
Accumulated depreciation and accumulated impairment losses of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance (258,712) (230,586)
Depreciation expenses (50,151) (50,656)
Impairment losses (1,247)  
Disposals and other decreases 16,380 18,437
Foreign currency translation differences (19,936) 4,092
Ending balance (313,664) (258,712)
Buildings and structures    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 470,089 521,403
Ending balance 471,325 470,089
Buildings and structures | Acquisition cost of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 716,831 741,898
Additions and other increases 18,549 18,118
Disposals and other decreases (13,115) (32,499)
Foreign currency translation differences 48,913 (10,687)
Ending balance 771,178 716,831
Buildings and structures | Accumulated depreciation and accumulated impairment losses of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance (246,742) (220,496)
Depreciation expenses (43,731) (44,571)
Impairment losses (1,247)  
Disposals and other decreases 10,344 14,587
Foreign currency translation differences (18,478) 3,738
Ending balance (299,853) (246,742)
Machinery and vehicles    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 11,373 11,950
Ending balance 11,777 11,373
Machinery and vehicles | Acquisition cost of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 23,275 21,880
Additions and other increases 7,331 6,867
Disposals and other decreases (7,719) (4,677)
Foreign currency translation differences 2,634 (795)
Ending balance 25,521 23,275
Machinery and vehicles | Accumulated depreciation and accumulated impairment losses of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance (11,902) (9,930)
Depreciation expenses (6,406) (6,065)
Impairment losses 0  
Disposals and other decreases 6,016 3,741
Foreign currency translation differences (1,454) 352
Ending balance (13,744) (11,902)
Tools, furniture, and fixtures    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 30 51
Ending balance 18 30
Tools, furniture, and fixtures | Acquisition cost of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance 98 211
Additions and other increases 2 0
Disposals and other decreases (20) (110)
Foreign currency translation differences 5 (2)
Ending balance 86 98
Tools, furniture, and fixtures | Accumulated depreciation and accumulated impairment losses of ROU Assets    
Disclosure of quantitative information about right-of-use assets [line items]    
Beginning balance (68) (160)
Depreciation expenses (15) (19)
Impairment losses 0  
Disposals and other decreases 20 109
Foreign currency translation differences (4) 2
Ending balance ¥ (67) ¥ (68)