v3.26.1
Property, plant and equipment - Summary of Changes In Property Plant And Equipment (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance ¥ 1,513,660 ¥ 1,522,640
Changes in carrying amount:    
Additions 349,271 346,903
Acquisitions through business combinations 1,464 17,954
Reclassifications (2,065) (3,650)
Disposals or classified as held for sale (38,208) (9,360)
Classified as held for distribution to owners (32,403)  
Depreciation (328,520) (347,066)
Impairment losses (37,484) (2,002)
Translation adjustment 25,811 (815)
Other 2,279 (10,944)
Total changes (59,855) (8,980)
Ending Balance 1,453,805 1,513,660
Land [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 88,625 85,946
Changes in carrying amount:    
Additions 495 2,815
Acquisitions through business combinations 0 258
Reclassifications 9 371
Disposals or classified as held for sale (584) (657)
Classified as held for distribution to owners (6,672)  
Translation adjustment 1,440 (162)
Other 0 54
Total changes (5,312) 2,679
Ending Balance 83,313 88,625
Buildings [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 481,455 443,783
Changes in carrying amount:    
Additions 14,448 19,701
Acquisitions through business combinations 396 12,511
Reclassifications 138,417 56,556
Disposals or classified as held for sale (19,167) (1,957)
Classified as held for distribution to owners (24,134)  
Depreciation (47,232) (45,722)
Impairment losses (9,800) (1,154)
Translation adjustment 12,139 (2,051)
Other (463) (212)
Total changes 64,604 37,672
Ending Balance 546,059 481,455
Machinery and equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 784,498 808,663
Changes in carrying amount:    
Additions 73,757 76,224
Acquisitions through business combinations 1,068 3,964
Reclassifications 136,416 213,401
Disposals or classified as held for sale (14,637) (5,762)
Classified as held for distribution to owners (1,535)  
Depreciation (281,288) (301,344)
Impairment losses (13,784) (645)
Translation adjustment 10,053 901
Other 3,970 (10,904)
Total changes (85,980) (24,165)
Ending Balance 698,518 784,498
Construction in progress [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 159,082 184,248
Changes in carrying amount:    
Additions 260,571 248,163
Acquisitions through business combinations 0 1,221
Reclassifications (276,907) (273,978)
Disposals or classified as held for sale (3,820) (984)
Classified as held for distribution to owners (62)  
Impairment losses (13,900) (203)
Translation adjustment 2,179 497
Other (1,228) 118
Total changes (33,167) (25,166)
Ending Balance 125,915 159,082
Gross carrying amount [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 4,061,368 3,856,202
Changes in carrying amount:    
Ending Balance 4,232,003 4,061,368
Gross carrying amount [member] | Land [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 88,662 85,983
Changes in carrying amount:    
Ending Balance 83,313 88,662
Gross carrying amount [member] | Buildings [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 1,093,460 1,033,758
Changes in carrying amount:    
Ending Balance 1,175,951 1,093,460
Gross carrying amount [member] | Machinery and equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 2,719,283 2,551,174
Changes in carrying amount:    
Ending Balance 2,831,795 2,719,283
Gross carrying amount [member] | Construction in progress [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 159,963 185,287
Changes in carrying amount:    
Ending Balance 140,944 159,963
Accumulated depreciation and impairment losses [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (2,547,708) (2,333,562)
Changes in carrying amount:    
Ending Balance (2,778,198) (2,547,708)
Accumulated depreciation and impairment losses [member] | Land [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (37) (37)
Changes in carrying amount:    
Ending Balance 0 (37)
Accumulated depreciation and impairment losses [member] | Buildings [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (612,005) (589,975)
Changes in carrying amount:    
Ending Balance (629,892) (612,005)
Accumulated depreciation and impairment losses [member] | Machinery and equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (1,934,785) (1,742,511)
Changes in carrying amount:    
Ending Balance (2,133,277) (1,934,785)
Accumulated depreciation and impairment losses [member] | Construction in progress [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (881) (1,039)
Changes in carrying amount:    
Ending Balance ¥ (15,029) ¥ (881)