Premises and Equipment (Tables)
 12 Months Ended
Mar. 31, 2022
Property, Plant and Equipment [Abstract]  
Components of Premises and Equipment
Premises and equipment at March 31, 2021 and 2022 consisted of the following:
 20212022
 (in millions)
Land¥379,560 ¥372,710 
Buildings765,341 766,945 
Equipment and furniture564,273 497,478 
Leasehold improvements303,164 255,679 
Construction in progress46,513 30,894 
Total2,058,851 1,923,706 
Less accumulated depreciation1,183,859 1,107,877 
Premises and equipment-net¥874,992 ¥815,829