SUBSEQUENT EVENTS - Additional Information (Details) - Subsequent Event ¥ in Billions	Apr. 15, 2021 JPY (¥) series
Subsequent Event [Line Items]
Number of Series of Senior Notes Issued Through a U.S. Public Debt Offering \| series	5
Senior notes
Subsequent Event [Line Items]
Debt Instrument, Face Amount	¥ 82.0
.633% senior notes due April 2031
Subsequent Event [Line Items]
Debt Instrument, Face Amount	¥ 30.0
Debt instrument, interest rate	0.633%
.844% senior notes due April 2033
Subsequent Event [Line Items]
Debt Instrument, Face Amount	¥ 12.0
Debt instrument, interest rate	0.844%
1.039% senior notes due April 2036
Subsequent Event [Line Items]
Debt Instrument, Face Amount	¥ 10.0
Debt instrument, interest rate	1.039%
1.264% senior notes due April 2041
Subsequent Event [Line Items]
Debt Instrument, Face Amount	¥ 10.0
Debt instrument, interest rate	1.264%
1.560% senior notes due April 2051
Subsequent Event [Line Items]
Debt Instrument, Face Amount	¥ 20.0
Debt instrument, interest rate	1.56%

Number of Series of Senior Notes Issued Through a U.S. Public Debt Offering

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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