Consolidated Balance Sheets (Parenthetical) - JPY (¥) ¥ in Millions	Mar. 31, 2020	Mar. 31, 2019
Statement of Financial Position [Abstract]
Marketable securities current pledged with secured parties	¥ 17,521	¥ 15,437
Investment securities pledged with secured parties	¥ 930,882	¥ 832,984
Common stock, par value
Common stock, shares authorized	3,600,000,000	3,600,000,000
Common stock, shares issued	1,261,058,781	1,271,230,341
Treasury stock, common stock shares	40,898,841	20,483,474

Face amount per share of no-par value common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

The fair value, as of the date of each statement of financial position presented, of investments which are not evidenced by ownership of securities, such as interests in partnerships or other forms of unincorporated entities, which are owned but transferred to serve as collateral for the payment of the related debt obligation, and that is reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge such ownership interests.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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- Definition

The fair value, as of the date of each statement of financial position presented, of other securities, classified as available for sale or held for investment, which are owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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No definition available.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29,30)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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