NOTES PAYABLE AND LEASE OBLIGATIONS - Additional Information (Detail) ¥ in Millions, $ in Millions		1 Months Ended									12 Months Ended
	Apr. 12, 2019 JPY (¥)	Apr. 30, 2020 USD ($)	Jan. 31, 2020 USD ($)	Sep. 30, 2019 JPY (¥)	Oct. 31, 2018 USD ($) series	Oct. 31, 2017 JPY (¥)	Dec. 31, 2016 USD ($)	Nov. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Feb. 29, 2012 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) series	Dec. 31, 2018 USD ($)	Dec. 31, 2020 JPY (¥)	Mar. 31, 2020 JPY (¥) series	Dec. 31, 2019 JPY (¥) series	Oct. 31, 2018 JPY (¥) series	Jan. 31, 2017 JPY (¥)	Sep. 30, 2016 USD ($) series	Mar. 31, 2015 USD ($)	Mar. 31, 2015 JPY (¥)	Nov. 30, 2014 JPY (¥)	Jun. 30, 2013 JPY (¥)	Feb. 29, 2012 JPY (¥)	Aug. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)
Debt Instrument [Line Items]
Number of series of senior notes issued through a U.S. public debt offering (in series) | series					3							4			4	4	3		2
Operating lease, cost | $											$ 56	$ 54	$ 73
Operating lease, payments | $											$ 54	$ 52
3.60% senior notes due April 2030
Debt Instrument [Line Items]
Debt instrument, interest rate		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.
Debt instrument, principal amount | $		$ 1,000
.300% senior notes due September 2025
Debt Instrument [Line Items]
Debt instrument, interest rate											0.30%			0.30%	0.30%
Debt instrument, principal amount														¥ 12,400	¥ 12,400
.550% senior notes due March 2030
Debt Instrument [Line Items]
Debt instrument, interest rate											0.55%			0.55%	0.55%
Debt instrument, principal amount														¥ 13,300	¥ 13,300
.750% senior notes due March 2032
Debt Instrument [Line Items]
Debt instrument, interest rate											0.75%			0.75%	0.75%
Debt instrument, principal amount														¥ 20,700	¥ 20,700
.830% senior notes due March 2035
Debt Instrument [Line Items]
Debt instrument, interest rate											0.83%			0.83%	0.83%
Debt instrument, principal amount														¥ 10,600	¥ 10,600
.500% senior notes due December 2029
Debt Instrument [Line Items]
Debt instrument, interest rate											0.50%	0.50%		0.50%		0.50%
Debt instrument, principal amount														¥ 12,600		¥ 12,600
.843% senior notes due December 2031
Debt Instrument [Line Items]
Debt instrument, interest rate											0.843%	0.843%		0.843%		0.843%
Debt instrument, principal amount														¥ 9,300		¥ 9,300
.934% senior notes due December 2034
Debt Instrument [Line Items]
Debt instrument, interest rate											0.934%	0.934%		0.934%		0.934%
Debt instrument, principal amount														¥ 9,800		¥ 9,800
1.122% senior notes due December 2039
Debt Instrument [Line Items]
Debt instrument, interest rate											1.122%	1.122%		1.122%		1.122%
Debt instrument, principal amount														¥ 6,300		¥ 6,300
Yen-denominated loans
Debt Instrument [Line Items]
Debt instrument, principal amount				¥ 30,000
Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, interest rate											0.43%	0.42%		0.43%		0.42%
Debt instrument, description of variable rate basis				bears interest at a rate per annum equal to the Tokyo interbank market rate (TIBOR), or alternate TIBOR, if applicable, plus the applicable TIBOR margin
Debt instrument, principal amount				¥ 5,000										¥ 5,000		¥ 5,000
Yen-denominated loan variable interest rate due September 2029
Debt Instrument [Line Items]
Debt instrument, interest rate											0.58%	0.57%		0.58%		0.57%
Debt instrument, description of variable rate basis				bears interest at a rate per annum equal to the TIBOR, or alternate TIBOR, if applicable, plus the applicable TIBOR margin
Debt instrument, principal amount				¥ 25,000										¥ 25,000		¥ 25,000
.963% subordinated bonds due April 2049
Debt Instrument [Line Items]
Debt instrument, interest rate	0.963%										0.963%	0.963%		0.963%		0.963%
Debt instrument, description of variable rate basis	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, principal amount	¥ 30,000													¥ 30,000		¥ 30,000
4.750% senior notes due January 2049
Debt Instrument [Line Items]
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.
Debt instrument, principal amount | $					$ 550
1.159% senior notes due October 2030
Debt Instrument [Line Items]
Debt instrument, interest rate					1.159%						1.159%	1.159%		1.159%		1.159%	1.159%
Debt instrument, principal amount														¥ 29,300		¥ 29,300	¥ 29,300
1.488% senior notes due October 2033
Debt Instrument [Line Items]
Debt instrument, interest rate					1.488%						1.488%	1.488%		1.488%		1.488%	1.488%
Debt instrument, principal amount														¥ 15,200		¥ 15,200	¥ 15,200
1.750% senior notes due October 2038
Debt Instrument [Line Items]
Debt instrument, interest rate					1.75%						1.75%	1.75%		1.75%		1.75%	1.75%
Debt instrument, principal amount														¥ 8,900		¥ 8,900	¥ 8,900
2.108% subordinated notes due October 2047
Debt Instrument [Line Items]
Debt instrument, interest rate						2.108%					2.108%	2.108%		2.108%		2.108%
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.
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 the interest of the debentures will be reset every five years at a rate of interest equal to the then-current JPY 5-year Swap Offered Rate plus 205 basis points.
Debt instrument, principal amount						¥ 60,000								¥ 60,000		¥ 60,000
.932% senior notes due January 2027
Debt Instrument [Line Items]
Debt instrument, interest rate											0.932%	0.932%		0.932%		0.932%		0.932%
Debt instrument, principal amount														¥ 60,000		¥ 60,000		¥ 60,000
2.875% senior notes due October 2026
Debt Instrument [Line Items]
Debt instrument, interest rate											2.875%	2.875%		2.875%		2.875%			2.875%
Debt instrument, principal amount | $																			$ 300
4.00% senior noted due October 2046
Debt Instrument [Line Items]
Debt instrument, interest rate											4.00%	4.00%		4.00%		4.00%			4.00%
Debt instrument, principal amount | $																			$ 400
3.25% senior notes due March 2025
Debt Instrument [Line Items]
Debt instrument, interest rate											3.25%	3.25%		3.25%		3.25%				3.25%	3.25%
Debt instrument effective principal amount after cross currency swap																					¥ 55,000
Debt instrument, principal amount | $																				$ 450
Debt instrument, effective interest rate																				0.82%	0.82%
3.625% senior notes due November 2024
Debt Instrument [Line Items]
Debt instrument, interest rate								3.625%			3.625%	3.625%		3.625%		3.625%						3.625%
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 treasury rate plus 20 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.
Debt instrument effective principal amount after cross currency swap																						¥ 85,300
Debt instrument, principal amount | $								$ 750
Debt instrument, effective interest rate								1.00%														1.00%
3.625% senior notes due June 2023
Debt Instrument [Line Items]
Debt instrument, interest rate									3.625%		3.625%	3.625%		3.625%		3.625%							3.625%
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 treasury rate plus 20 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.
Debt instrument effective principal amount after cross currency swap																							¥ 69,800
Debt instrument, principal amount | $									$ 700
Debt instrument, effective interest rate									1.50%														1.50%
4.00% senior notes paid January 2020
Debt Instrument [Line Items]
Repayments of debt | $			$ 350
Debt instrument, interest rate			4.00%							4.00%		4.00%				4.00%								4.00%
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 principal amount of the notes or (ii) the present value of the remaining scheduled payments of principal and interest to be redeemed, discounted to the redemption date, plus accrued and unpaid interest.
Debt instrument effective principal amount after cross currency swap																								¥ 27,000
Debt instrument, principal amount | $										$ 350
Debt instrument, effective interest rate										2.07%														2.07%
Expense on extinguishment of debt | $											$ 15
6.90% senior notes due December 2039
Debt Instrument [Line Items]
Repayments of debt | $							$ 176
Debt instrument, interest rate							6.90%				6.90%	6.90%		6.90%		6.90%
Debt instrument, principal amount | $																										$ 400
6.45% senior notes due August 2040
Debt Instrument [Line Items]
Repayments of debt | $							$ 193
Debt instrument, interest rate							6.45%				6.45%	6.45%		6.45%		6.45%
Debt instrument, principal amount | $																									$ 450
Senior Notes due 2039 and 2040
Debt Instrument [Line Items]
Expense on extinguishment of debt | $							$ 137
Senior Notes
Debt Instrument [Line Items]
Debt instrument, principal amount															¥ 57,000	¥ 38,000	¥ 53,400		$ 700
Notes Payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount | $											$ 0	$ 0
Lower Limit | Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.30%
Lower Limit | Yen-denominated loan variable interest rate due September 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.45%
Upper Limit | Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.70%
Upper Limit | Yen-denominated loan variable interest rate due September 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.00%
Line of Credit
Debt Instrument [Line Items]
Debt instrument, debt default, amount | $											$ 0	$ 0