v3.25.2
Structured entities - Summary of Unconsolidated Structured Entities (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2025
Mar. 31, 2024
Disclosure of unconsolidated structured entities [line items]    
Maximum exposure to loss ¥ 1,424,083 ¥ 1,182,927
Investments And Advances In The Financial Services Segment Current [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities 22,071 11,365
Investments And Advances In The Financial Services Segment Noncurrent [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities 1,358,517 1,124,584
Other Current Financial Assets [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities 21,429 24,836
Securitized Products [Member]    
Disclosure of unconsolidated structured entities [line items]    
Maximum exposure to loss 547,861 461,309
Securitized Products [Member] | Investments And Advances In The Financial Services Segment Noncurrent [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities 547,861 461,309
Foreign Corporate Bonds [Member]    
Disclosure of unconsolidated structured entities [line items]    
Maximum exposure to loss [1] 242,006 217,935
Foreign Corporate Bonds [Member] | Investments And Advances In The Financial Services Segment Current [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities [1] 22,071 11,365
Foreign Corporate Bonds [Member] | Investments And Advances In The Financial Services Segment Noncurrent [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities [1] 219,935 206,570
Investment funds [member]    
Disclosure of unconsolidated structured entities [line items]    
Maximum exposure to loss [2] 634,216 503,683
Investment funds [member] | Investments And Advances In The Financial Services Segment Noncurrent [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities [2] 590,721 456,705
Investment funds [member] | Other Current Financial Assets [Member]    
Disclosure of unconsolidated structured entities [line items]    
Assets recognised in entity's financial statements in relation to structured entities [2] ¥ 21,429 ¥ 24,836
[1] Foreign corporate bonds primarily include repackaged bonds.
[2] Other investments primarily include investment funds.