Effective interest rate percentage on a debt instrument after entering into an interest rate swap.

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Debt Instrument Effective Principal Amount After Cross Currency Swap

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

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Amount of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Earliest date before maturity when the issuer can call the outstanding debt instrument for repayment or conversion to equity, in CCYY-MM-DD format.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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

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

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Description of debt redemption features under terms of the debt agreement.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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NOTES PAYABLE - Additional Information (Detail) $ in Millions, ¥ in Billions		1 Months Ended						12 Months Ended
	Apr. 12, 2019 JPY (¥)	Sep. 30, 2019 JPY (¥)	Oct. 31, 2018 USD ($) series	Oct. 31, 2017 JPY (¥)	Dec. 31, 2016 USD ($)	Nov. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Dec. 31, 2019 USD ($) series	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 JPY (¥) series	Dec. 31, 2018 JPY (¥)	Oct. 31, 2018 JPY (¥) series	Jan. 31, 2017 JPY (¥)	Sep. 30, 2016 USD ($) series	Mar. 31, 2015 USD ($)	Mar. 31, 2015 JPY (¥)	Nov. 30, 2014 JPY (¥)	Jun. 30, 2013 JPY (¥)	Feb. 29, 2012 USD ($)	Feb. 29, 2012 JPY (¥)	Aug. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)
Debt Instrument [Line Items]
Operating Lease, Cost \| $								$ 54	$ 73	$ 75
Number of series of senior notes issued through a U.S. public debt offering (in series) \| series			3					4			4		3		2
Operating lease, payments \| $								$ 52
.500% senior notes due December 2029
Debt Instrument [Line Items]
Debt instrument, interest rate								0.50%			0.50%
Debt instrument, principal amount											¥ 12.6
.843% senior notes due December 2031
Debt Instrument [Line Items]
Debt instrument, interest rate								0.843%			0.843%
Debt instrument, principal amount											¥ 9.3
.934% senior notes due December 2034
Debt Instrument [Line Items]
Debt instrument, interest rate								0.934%			0.934%
Debt instrument, principal amount											¥ 9.8
1.122% senior notes due December 2039
Debt Instrument [Line Items]
Debt instrument, interest rate								1.122%			1.122%
Debt instrument, principal amount											¥ 6.3
Yen-denominated loans
Debt Instrument [Line Items]
Debt instrument, principal amount		¥ 30.0
Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, interest rate								0.42%			0.42%	0.32%
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		¥ 5.0									¥ 5.0	¥ 5.0
Yen-denominated loan variable interest rate due September 2029
Debt Instrument [Line Items]
Debt instrument, interest rate								0.57%			0.57%	0.47%
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		¥ 25.0									¥ 25.0	¥ 25.0
.963% subordinated bonds due April 2049
Debt Instrument [Line Items]
Debt instrument, interest rate	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	¥ 30.0										¥ 30.0
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%
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%
Debt instrument, principal amount											¥ 29.3	¥ 29.3	¥ 29.3
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%
Debt instrument, principal amount											¥ 15.2	¥ 15.2	¥ 15.2
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%
Debt instrument, principal amount											¥ 8.9	¥ 8.9	¥ 8.9
2.108% subordinated notes due October 2047
Debt Instrument [Line Items]
Debt instrument, interest rate				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, call date, earliest				Oct. 23, 2027
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				¥ 60.0							¥ 60.0	¥ 60.0
.932% senior notes due January 2027
Debt Instrument [Line Items]
Debt instrument, interest rate								0.932%			0.932%	0.932%		0.932%
Debt instrument, principal amount											¥ 60.0	¥ 60.0		¥ 60.0
2.875% senior notes due October 2026
Debt Instrument [Line Items]
Debt instrument, interest rate								2.875%			2.875%	2.875%			2.875%
Debt instrument, principal amount \| $															$ 300
4.00% senior notes due October 2046
Debt Instrument [Line Items]
Debt instrument, interest rate								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%
Debt instrument effective principal amount after cross currency swap																	¥ 55.0
Debt instrument, principal amount \| $								$ 450								$ 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%
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																		¥ 85.3
Debt instrument, principal amount \| $						$ 750		$ 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%
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																			¥ 69.8
Debt instrument, principal amount \| $							$ 700	$ 700
Debt instrument, effective interest rate							1.50%												1.50%
4.00% senior notes due February 2022
Debt Instrument [Line Items]
Debt instrument, interest rate								4.00%			4.00%	4.00%								4.00%	4.00%
Debt instrument effective principal amount after cross currency swap																					¥ 27.0
Debt instrument, principal amount \| $								$ 350												$ 350
Debt instrument, effective interest rate																				2.07%	2.07%
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%
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%
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											¥ 38.0		¥ 53.4		$ 700
Notes Payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount \| $								$ 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