v3.25.2
Property, plant and equipment - Summary of Changes In Property Plant And Equipment (Detail) - JPY (¥)
¥ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance ¥ 1,522,640 ¥ 1,344,864
Changes in carrying amount:    
Additions 346,903 495,888
Acquisitions through business combinations 17,954 1,396
Reclassifications (3,650) (2,681)
Disposals or classified as held for sale (9,360) (9,268)
Depreciation (347,066) (321,588)
Impairment losses (2,002) (345)
Translation adjustment (815) 31,093
Other (10,944) (16,719)
Total changes (8,980) 177,776
Ending Balance 1,513,660 1,522,640
Land [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 85,946 79,254
Changes in carrying amount:    
Additions 2,815 6,068
Acquisitions through business combinations 258  
Reclassifications 371 616
Disposals or classified as held for sale (657) (2,077)
Translation adjustment (162) 2,085
Other 54  
Total changes 2,679 6,692
Ending Balance 88,625 85,946
Buildings [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 443,783 379,303
Changes in carrying amount:    
Additions 19,701 14,886
Acquisitions through business combinations 12,511 912
Reclassifications 56,556 76,731
Disposals or classified as held for sale (1,957) (2,361)
Depreciation (45,722) (39,781)
Impairment losses (1,154) (76)
Translation adjustment (2,051) 15,913
Other (212) (1,744)
Total changes 37,672 64,480
Ending Balance 481,455 443,783
Machinery and equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 808,663 686,172
Changes in carrying amount:    
Additions 76,224 100,199
Acquisitions through business combinations 3,964 472
Reclassifications 213,401 314,967
Disposals or classified as held for sale (5,762) (3,416)
Depreciation (301,344) (281,807)
Impairment losses (645) (258)
Translation adjustment 901 7,366
Other (10,904) (15,032)
Total changes (24,165) 122,491
Ending Balance 784,498 808,663
Construction in progress [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 184,248 200,135
Changes in carrying amount:    
Additions 248,163 374,735
Acquisitions through business combinations 1,221 12
Reclassifications (273,978) (394,995)
Disposals or classified as held for sale (984) (1,414)
Impairment losses (203) (11)
Translation adjustment 497 5,729
Other 118 57
Total changes (25,166) (15,887)
Ending Balance 159,082 184,248
Gross carrying amount [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 3,856,202 3,403,756
Changes in carrying amount:    
Ending Balance 4,061,368 3,856,202
Gross carrying amount [member] | Land [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 85,983 79,291
Changes in carrying amount:    
Ending Balance 88,662 85,983
Gross carrying amount [member] | Buildings [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 1,033,758 921,156
Changes in carrying amount:    
Ending Balance 1,093,460 1,033,758
Gross carrying amount [member] | Machinery and equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 2,551,174 2,202,010
Changes in carrying amount:    
Ending Balance 2,719,283 2,551,174
Gross carrying amount [member] | Construction in progress [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance 185,287 201,299
Changes in carrying amount:    
Ending Balance 159,963 185,287
Accumulated depreciation and impairment losses [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (2,333,562) (2,058,892)
Changes in carrying amount:    
Ending Balance (2,547,708) (2,333,562)
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 (37) (37)
Accumulated depreciation and impairment losses [member] | Buildings [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (589,975) (541,853)
Changes in carrying amount:    
Ending Balance (612,005) (589,975)
Accumulated depreciation and impairment losses [member] | Machinery and equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (1,742,511) (1,515,838)
Changes in carrying amount:    
Ending Balance (1,934,785) (1,742,511)
Accumulated depreciation and impairment losses [member] | Construction in progress [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning Balance (1,039) (1,164)
Changes in carrying amount:    
Ending Balance ¥ (881) ¥ (1,039)