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NOTES PAYABLE AND LEASE OBLIGATIONS - Additional Information (Detail) $ in Millions, ¥ in Billions | 1 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2023 JPY (¥) | Aug. 31, 2022 JPY (¥) | Mar. 31, 2021 USD ($) | Apr. 30, 2020 USD ($) | Apr. 30, 2019 | Oct. 31, 2018 JPY (¥) series | Oct. 31, 2017 JPY (¥) | Dec. 31, 2016 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2024 JPY (¥) | Dec. 31, 2024 USD ($) | Apr. 01, 2024 USD ($) | Mar. 31, 2024 JPY (¥) series | Dec. 31, 2023 USD ($) | Sep. 30, 2022 JPY (¥) series | Apr. 30, 2021 JPY (¥) series | Mar. 31, 2020 JPY (¥) series | Dec. 31, 2019 JPY (¥) series | Apr. 01, 2019 JPY (¥) | Oct. 31, 2018 USD ($) series | Jan. 31, 2017 JPY (¥) | Sep. 30, 2016 USD ($) series | Aug. 31, 2010 USD ($) | Dec. 31, 2009 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Senior Notes Issued Through a Private Placement (in series) | series |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 |  |  |  |  |  |  |  |  |  |  |
Number of series of senior notes issued through a U.S. public debt offering (in series) | series |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  | 3 |  | 4 | 5 | 4 | 4 |  | 3 |  | 2 |  |
Interest expense on debt | $ |  |  |  |  |  |  |  |  | $ 194 | $ 190 | $ 217 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease, cost | $ |  |  |  |  |  |  |  |  | 43 | 49 | 52 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease, payments | $ |  |  |  |  |  |  |  |  | $ 41 | $ 48 | $ 49 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Private Placement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 75.0 |  |  |  |  |  |  |  |  |  |  |
Senior notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount |  |  |  |  |  | ¥ 53.4 |  |  |  |  |  |  |  |  | ¥ 48.6 |  | ¥ 73.0 | ¥ 82.0 | ¥ 57.0 | ¥ 38.0 |  |  |  | $ 700 |  |
3.60% senior notes due April 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  |  | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 3.60% |  |  | 3.60% |  |  |  |  |  |  |  | 3.60% | 3.60% |  |  | 3.60% |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption, description |  |  |  | These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 45 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
.300% senior notes due September 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 12.4 |  |  |  |  |  |  |  |  |  |  | ¥ 12.4 |  |  |  |  |  |  | ¥ 12.4 |  |  |  |  |  |  |
Debt instrument, interest rate | 0.30% |  |  |  |  |  |  |  |  |  |  | 0.30% | 0.30% |  |  | 0.30% |  |  | 0.30% |  |  |  |  |  |  |
.550% senior notes due March 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 13.3 |  |  |  |  |  |  |  |  |  |  | ¥ 13.3 |  |  |  |  |  |  | ¥ 13.3 |  |  |  |  |  |  |
Debt instrument, interest rate | 0.55% |  |  |  |  |  |  |  |  |  |  | 0.55% | 0.55% |  |  | 0.55% |  |  | 0.55% |  |  |  |  |  |  |
.750% senior notes due March 2032 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 20.7 |  |  |  |  |  |  |  |  |  |  | ¥ 20.7 |  |  |  |  |  |  | ¥ 20.7 |  |  |  |  |  |  |
Debt instrument, interest rate | 0.75% |  |  |  |  |  |  |  |  |  |  | 0.75% | 0.75% |  |  | 0.75% |  |  | 0.75% |  |  |  |  |  |  |
.830% senior notes due March 2035 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 10.6 |  |  |  |  |  |  |  |  |  |  | ¥ 10.6 |  |  |  |  |  |  | ¥ 10.6 |  |  |  |  |  |  |
Debt instrument, interest rate | 0.83% |  |  |  |  |  |  |  |  |  |  | 0.83% | 0.83% |  |  | 0.83% |  |  | 0.83% |  |  |  |  |  |  |
.500% senior notes due December 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 12.6 |  |  |  |  |  |  |  |  |  |  | ¥ 12.6 |  |  |  |  |  |  |  | ¥ 12.6 |  |  |  |  |  |
Debt instrument, interest rate | 0.50% |  |  |  |  |  |  |  |  |  |  | 0.50% | 0.50% |  |  | 0.50% |  |  |  | 0.50% |  |  |  |  |  |
.843% senior notes due December 2031 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 9.3 |  |  |  |  |  |  |  |  |  |  | ¥ 9.3 |  |  |  |  |  |  |  | ¥ 9.3 |  |  |  |  |  |
Debt instrument, interest rate | 0.843% |  |  |  |  |  |  |  |  |  |  | 0.843% | 0.843% |  |  | 0.843% |  |  |  | 0.843% |  |  |  |  |  |
.934% senior notes due December 2034 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 9.8 |  |  |  |  |  |  |  |  |  |  | ¥ 9.8 |  |  |  |  |  |  |  | ¥ 9.8 |  |  |  |  |  |
Debt instrument, interest rate | 0.934% |  |  |  |  |  |  |  |  |  |  | 0.934% | 0.934% |  |  | 0.934% |  |  |  | 0.934% |  |  |  |  |  |
1.122% senior notes due December 2039 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 6.3 |  |  |  |  |  |  |  |  |  |  | ¥ 6.3 |  |  |  |  |  |  |  | ¥ 6.3 |  |  |  |  |  |
Debt instrument, interest rate | 1.122% |  |  |  |  |  |  |  |  |  |  | 1.122% | 1.122% |  |  | 1.122% |  |  |  | 1.122% |  |  |  |  |  |
.963% subordinated bonds paid April 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 30.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | ¥ 30.0 |  |  |  |  |
Debt instrument, interest rate | 0.963% |  |  |  |  |  |  |  |  |  |  |  |  | 0.963% |  | 0.963% |  |  |  |  | 0.963% |  |  |  |  |
Debt instrument, interest rate terms |  |  |  |  | These bonds bear interest at a fixed rate of .963% per annum and then at six-month Euro Yen LIBOR plus an applicable spread on and after the day immediately following April 18, 2024. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption, description |  |  |  |  | The bonds will be callable on each interest payment date on and after April 18, 2024. In November 2019, ALIJ amended the bonds to change their duration from perpetual to a stated maturity date of April 16, 2049 and to remove provisions that permitted ALIJ to defer payments of interest under certain circumstances. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount redeemed | $ |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 30,000 |  |  |  |  |  |  |  |  |  |  |  |
4.750% senior notes due January 2049 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 550 |  |  |  |
Debt instrument, interest rate | 4.75% |  |  |  |  | 4.75% |  |  |  |  |  | 4.75% | 4.75% |  |  | 4.75% |  |  |  |  |  | 4.75% |  |  |  |
Debt instrument, redemption, description |  |  |  |  |  | These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 25 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
1.159% senior notes due October 2030 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 29.3 |  |  |  |  | ¥ 29.3 |  |  |  |  |  | ¥ 29.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.159% |  |  |  |  | 1.159% |  |  |  |  |  | 1.159% | 1.159% |  |  | 1.159% |  |  |  |  |  | 1.159% |  |  |  |
1.488% senior notes due October 2033 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 15.2 |  |  |  |  | ¥ 15.2 |  |  |  |  |  | ¥ 15.2 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.488% |  |  |  |  | 1.488% |  |  |  |  |  | 1.488% | 1.488% |  |  | 1.488% |  |  |  |  |  | 1.488% |  |  |  |
1.750% senior notes due October 2038 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 8.9 |  |  |  |  | ¥ 8.9 |  |  |  |  |  | ¥ 8.9 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.75% |  |  |  |  | 1.75% |  |  |  |  |  | 1.75% | 1.75% |  |  | 1.75% |  |  |  |  |  | 1.75% |  |  |  |
2.108% subordinated notes due October 2047 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 60.0 |  |  |  |  |  | ¥ 60.0 |  |  |  |  | ¥ 60.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 2.108% |  |  |  |  |  | 2.108% |  |  |  |  | 2.108% | 2.108% |  |  | 2.108% |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate terms |  |  |  |  |  |  | The debentures bear interest at an initial rate of 2.108% per annum through October 22, 2027, or earlier redemption. Thereafter, the rate of interest of the debentures will be reset every five years to a rate of interest equal to the then-current JPY 5-year Swap Offered Rate plus 205 basis points. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption, description |  |  |  |  |  |  | The debentures are redeemable (i) at any time, in whole but not in part, upon the occurrence of certain tax events or certain rating agency events, as specified in the indenture governing the terms of the debentures or (ii) on or after October 23, 2027, in whole or in part, at a redemption price equal to their principal amount plus accrued and unpaid interest to, but excluding, the date of redemption. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
.932% senior notes due January 2027 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 60.0 |  |  |  |  |  |  |  |  |  |  | ¥ 60.0 |  |  |  |  |  |  |  |  |  |  | ¥ 60.0 |  |  |
Debt instrument, interest rate | 0.932% |  |  |  |  |  |  |  |  |  |  | 0.932% | 0.932% |  |  | 0.932% |  |  |  |  |  |  | 0.932% |  |  |
2.875% senior notes due October 2026 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 300 |  |
Debt instrument, interest rate | 2.875% |  |  |  |  |  |  |  |  |  |  | 2.875% | 2.875% |  |  | 2.875% |  |  |  |  |  |  |  | 2.875% |  |
4.00% senior noted due October 2046 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 400 |  |
Debt instrument, interest rate | 4.00% |  |  |  |  |  |  |  |  |  |  | 4.00% | 4.00% |  |  | 4.00% |  |  |  |  |  |  |  | 4.00% |  |
6.90% senior notes due December 2039 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 400
Debt instrument, interest rate | 6.90% |  |  |  |  |  |  | 6.90% |  |  |  | 6.90% | 6.90% |  |  | 6.90% |  |  |  |  |  |  |  |  |  |
Repayments of debt | $ |  |  |  |  |  |  |  | $ 176 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
6.45% senior notes due August 2040 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 450 |
Debt instrument, interest rate | 6.45% |  |  |  |  |  |  | 6.45% |  |  |  | 6.45% | 6.45% |  |  | 6.45% |  |  |  |  |  |  |  |  |  |
Repayments of debt | $ |  |  |  |  |  |  |  | $ 193 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes due 2039 and 2040 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expense on extinguishment of debt | $ |  |  |  |  |  |  |  | $ (137) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
.633% senior notes due April 2031 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 30.0 |  |  |  |  |  |  |  |  |  |  | ¥ 30.0 |  |  |  |  |  | ¥ 30.0 |  |  |  |  |  |  |  |
Debt instrument, interest rate | 0.633% |  |  |  |  |  |  |  |  |  |  | 0.633% | 0.633% |  |  | 0.633% |  | 0.633% |  |  |  |  |  |  |  |
.844% senior notes due April 2033 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 12.0 |  |  |  |  |  |  |  |  |  |  | ¥ 12.0 |  |  |  |  |  | ¥ 12.0 |  |  |  |  |  |  |  |
Debt instrument, interest rate | 0.844% |  |  |  |  |  |  |  |  |  |  | 0.844% | 0.844% |  |  | 0.844% |  | 0.844% |  |  |  |  |  |  |  |
1.039% senior notes due April 2036 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 10.0 |  |  |  |  |  |  |  |  |  |  | ¥ 10.0 |  |  |  |  |  | ¥ 10.0 |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.039% |  |  |  |  |  |  |  |  |  |  | 1.039% | 1.039% |  |  | 1.039% |  | 1.039% |  |  |  |  |  |  |  |
1.264% senior notes due April 2041 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 10.0 |  |  |  |  |  |  |  |  |  |  | ¥ 10.0 |  |  |  |  |  | ¥ 10.0 |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.264% |  |  |  |  |  |  |  |  |  |  | 1.264% | 1.264% |  |  | 1.264% |  | 1.264% |  |  |  |  |  |  |  |
1.560% senior notes due April 2051 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 20.0 |  |  |  |  |  |  |  |  |  |  | ¥ 20.0 |  |  |  |  |  | ¥ 20.0 |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.56% |  |  |  |  |  |  |  |  |  |  | 1.56% | 1.56% |  |  | 1.56% |  | 1.56% |  |  |  |  |  |  |  |
1.125% senior notes due March 2026 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | $ |  |  | $ 400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.125% |  | 1.125% |  |  |  |  |  |  |  |  | 1.125% | 1.125% |  |  | 1.125% |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption, description |  |  | These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 10 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
1.075% senior notes due September 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 33.4 |  |  |  |  |  |  |  |  |  |  | ¥ 33.4 |  |  |  |  | ¥ 33.4 |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.075% |  |  |  |  |  |  |  |  |  |  | 1.075% | 1.075% |  |  | 1.075% | 1.075% |  |  |  |  |  |  |  |  |
1.320% senior notes due December 2032 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 21.1 |  |  |  |  |  |  |  |  |  |  | ¥ 21.1 |  |  |  |  | ¥ 21.1 |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.32% |  |  |  |  |  |  |  |  |  |  | 1.32% | 1.32% |  |  | 1.32% | 1.32% |  |  |  |  |  |  |  |  |
1.594% senior notes due September 2037 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 6.5 |  |  |  |  |  |  |  |  |  |  | ¥ 6.5 |  |  |  |  | ¥ 6.5 |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.594% |  |  |  |  |  |  |  |  |  |  | 1.594% | 1.594% |  |  | 1.594% | 1.594% |  |  |  |  |  |  |  |  |
2.144% senior notes due September 2052 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 12.0 |  |  |  |  |  |  |  |  |  |  | ¥ 12.0 |  |  |  |  | ¥ 12.0 |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 2.144% |  |  |  |  |  |  |  |  |  |  | 2.144% | 2.144% |  |  | 2.144% | 2.144% |  |  |  |  |  |  |  |  |
1.958% subordinated bonds due December 2053 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 30.0 |  |  |  |  |  |  |  |  |  |  | ¥ 30.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 1.958% |  |  |  |  |  |  |  |  |  |  | 1.958% | 1.958% |  |  | 1.958% |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate terms | The bonds bear interest at an initial rate of 1.958% per annum until December 5, 2028. Thereafter, the rate of interest of the bonds will be reset every five years to a rate of interest equal to the then-current five-year JGB rate plus (i) 1.650% per annum on and after the day immediately following December 5, 2028 to December 5, 2033, and (ii) 2.650% per annum on and after the day immediately following December 5, 2033 to December 5, 2053. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, redemption, description | The bonds are redeemable, in whole but not in part, (i) at any time upon the occurrence of certain regulatory or tax events, as specified in the indenture governing the terms of the bonds or (ii) on each interest rate reset date on or after December 5, 2028. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Yen-denominated loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount |  | ¥ 107.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Yen-denominated loan variable interest rate due August 2027 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 11.7 | 11.7 |  |  |  |  |  |  |  |  |  | ¥ 11.7 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 0.35% |  |  |  |  |  |  |  |  |  |  | 0.84% | 0.84% |  |  | 0.35% |  |  |  |  |  |  |  |  |  |
Yen-denominated loan variable interest rate due August 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 25.3 | 25.3 |  |  |  |  |  |  |  |  |  | ¥ 25.3 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 0.45% |  |  |  |  |  |  |  |  |  |  | 0.94% | 0.94% |  |  | 0.45% |  |  |  |  |  |  |  |  |  |
Yen-denominated loan variable interest rate due August 2032 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, principal amount | ¥ 70.0 | ¥ 70.0 |  |  |  |  |  |  |  |  |  | ¥ 70.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate | 0.60% |  |  |  |  |  |  |  |  |  |  | 1.09% | 1.09% |  |  | 0.60% |  |  |  |  |  |  |  |  |  |
Notes Payable |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, debt default, amount | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  | $ 0 |  |  |  |  |  |  |  |  |  |
Line of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, debt default, amount | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  | $ 0 |  |  |  |  |  |  |  |  |  |
Lower Limit | Yen-denominated loan variable interest rate due August 2027 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.225% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lower Limit | Yen-denominated loan variable interest rate due August 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.325% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lower Limit | Yen-denominated loan variable interest rate due August 2032 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.475% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upper Limit | Yen-denominated loan variable interest rate due August 2027 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.625% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upper Limit | Yen-denominated loan variable interest rate due August 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.725% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upper Limit | Yen-denominated loan variable interest rate due August 2032 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 1.025% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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