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

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Minimum principal amount outstanding following partial redemption

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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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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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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Gross amount of debt extinguished.

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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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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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The cash outflow associated with security instruments that either represent a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes repayments of (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c).

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NOTES PAYABLE - Additional Information (Detail)	1 Months Ended																	12 Months Ended
NOTES PAYABLE - Additional Information (Detail)	Aug. 31, 2015 USD ($)	Aug. 31, 2015 JPY (¥)	Jul. 31, 2015 USD ($)	Jul. 31, 2015 JPY (¥)	Apr. 30, 2015 USD ($)	Mar. 31, 2015 USD ($) series	Nov. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)	Oct. 31, 2012 USD ($)	Sep. 30, 2012 USD ($)	Jul. 31, 2012 USD ($)	Feb. 29, 2012 USD ($) series	Jul. 31, 2011 JPY (¥) series	Aug. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	May. 31, 2009 USD ($)	Sep. 30, 2006 JPY (¥)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2009 JPY (¥)	Dec. 31, 2015 JPY (¥)	Mar. 31, 2015 JPY (¥) series	Dec. 31, 2014 JPY (¥)	Nov. 30, 2014 JPY (¥)	Jun. 30, 2013 JPY (¥)	Oct. 31, 2012 JPY (¥)	Sep. 30, 2012 JPY (¥)	Feb. 29, 2012 JPY (¥) series
Debt Instrument [Line Items]
Number of series of senior notes issued through a U.S. public debt offering (in series) \| series						2						2	3										2						2
Principal payments under debt obligations																		$ 1,272,000,000	$ 335,000,000	$ 0
3.45% senior notes paid August 2015
Debt Instrument [Line Items]
Repayments of Debt	$ 300,000,000
Debt instrument, interest rate																			3.45%					3.45%
Debt Instrument, term														5 years
Debt instrument, principal amount														$ 300,000,000
2.65% senior notes due February 2017
Debt Instrument [Line Items]
Debt instrument, interest rate											2.65%	2.65%						2.65%	2.65%			2.65%		2.65%					2.65%
Debt Instrument, term											5 years	5 years
Debt instrument effective principal amount after cross currency swap \| ¥																													¥ 30,900,000,000
Debt instrument, principal amount											$ 250,000,000	$ 400,000,000						$ 400,000,000
Debt instrument, effective interest rate												1.22%																	1.22%
8.50% senior notes due May 2019
Debt Instrument [Line Items]
Debt instrument, interest rate					8.50%														8.50%					8.50%
Debt Instrument, term																10 years
Debt instrument, principal amount																$ 850,000,000
Principal payments under debt obligations					$ 850,000,000
Expense on extinguishment of debt, make-whole premium					$ 230,000,000													$ 230,000,000
2.40% senior notes due March 2020
Debt Instrument [Line Items]
Debt instrument, interest rate						2.40%												2.40%				2.40%	2.40%
Debt Instrument, term						5 years
Debt instrument effective principal amount after cross currency swap \| ¥																							¥ 67,000,000,000
Debt instrument, principal amount						$ 550,000,000												$ 550,000,000
Debt instrument, effective interest rate						0.24%																	0.24%
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%					4.00%
Debt Instrument, term												10 years
Debt instrument effective principal amount after cross currency swap \| ¥																													¥ 27,000,000,000
Debt instrument, principal amount												$ 350,000,000						$ 350,000,000
Debt instrument, effective interest rate												2.07%																	2.07%
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, term								10 years
Debt Instrument, redemption, description								These notes are redeemable at our 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 \| ¥																										¥ 69,800,000,000
Debt instrument, principal amount								$ 700,000,000										$ 700,000,000
Debt instrument, effective interest rate								1.50%																		1.50%
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, term							10 years
Debt Instrument, redemption, description							These notes are redeemable at our 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 \| ¥																									¥ 85,300,000,000
Debt instrument, principal amount							$ 750,000,000											$ 750,000,000
Debt instrument, effective interest rate							1.00%																		1.00%
3.25% senior notes due March 2025
Debt Instrument [Line Items]
Debt instrument, interest rate						3.25%												3.25%				3.25%	3.25%
Debt Instrument, term						10 years
Debt instrument effective principal amount after cross currency swap \| ¥																							¥ 55,000,000,000
Debt instrument, principal amount						$ 450,000,000												$ 450,000,000
Debt instrument, effective interest rate						0.82%																	0.82%
6.90% senior notes due December 2039
Debt Instrument [Line Items]
Debt instrument, interest rate																		6.90%	6.90%			6.90%		6.90%
Debt Instrument, term															30 years
Debt instrument, principal amount															$ 400,000,000
6.45% senior notes due August 2040
Debt Instrument [Line Items]
Debt instrument, interest rate																		6.45%	6.45%			6.45%		6.45%
Debt Instrument, term														30 years
Debt instrument, principal amount														$ 450,000,000
5.50% subordinated notes due September 2052
Debt Instrument [Line Items]
Debt instrument, interest rate									5.50%	5.50%								5.50%	5.50%			5.50%		5.50%			5.50%	5.50%
Debt Instrument, term										40 years
Debt instrument effective principal amount after cross currency swap \| ¥																											¥ 3,900,000,000	¥ 35,300,000,000
Debt instrument, principal amount									$ 50,000,000	$ 450,000,000								$ 500,000,000
Minimum prinicipal amount outstanding following partial redemption																		$ 25,000,000
Debt instrument, effective interest rate									4.42%	4.41%																	4.42%	4.41%
Derivative, Term of Contract									5 years	5 years
2.26% yen-denominated Uridashi notes due September 2016
Debt Instrument [Line Items]
Debt instrument, interest rate																		2.26%	2.26%			2.26%		2.26%
Debt Instrument, term																	10 years
Principal payments under debt obligations \| ¥																					¥ 1,400,000,000
Debt instrument, principal amount \| ¥																	¥ 10,000,000,000					¥ 8,000,000,000		¥ 8,000,000,000
Extinguishment of notes \| ¥																					2,000,000,000
Expense on extinguishment of debt, make-whole premium \| ¥																					¥ (600,000,000)
1.84% yen-denominated Samurai notes due July 2016
Debt Instrument [Line Items]
Debt instrument, interest rate													1.84%					1.84%	1.84%			1.84%		1.84%
Debt Instrument, term													5 years
Debt instrument, principal amount \| ¥													¥ 15,800,000,000									¥ 15,800,000,000		¥ 15,800,000,000
3.60% yen-denominated loan paid July 2015
Debt Instrument [Line Items]
Repayments of Debt			$ 81,000,000	¥ 10,000,000,000
Debt instrument, interest rate																			3.60%					3.60%
Debt instrument, principal amount \| ¥																								¥ 10,000,000,000
3.00% yen-denominated loan paid August 2015
Debt Instrument [Line Items]
Repayments of Debt	$ 41,000,000	¥ 5,000,000,000
Debt instrument, interest rate																			3.00%					3.00%
Debt instrument, principal amount \| ¥																								¥ 5,000,000,000
1.47% yen-denominated Samurai notes paid July 2014
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥													28,700,000,000
Variable interest rate yen-denominated Samurai notes paid July 2014
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥													5,500,000,000
Senior Notes
Debt Instrument [Line Items]
Debt instrument, principal amount						$ 1,000,000,000						$ 750,000,000
Yen-denominated Samurai notes
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥													¥ 50,000,000,000
Notes Payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount																		$ 0	$ 0
Lines of credit
Debt Instrument [Line Items]
Debt instrument, debt default, amount																		$ 0	$ 0
50 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity \| ¥																						50,000,000,000
55 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility term																		5 years
Line of credit facility, maximum borrowing capacity \| ¥																						55,000,000,000
Line of credit facility, interest rate description																		Borrowings bear interest at a rate per annum equal to, at our option, either (a) a eurocurrency rate determined by reference to the London Interbank Offered Rate (LIBOR) for the interest period relevant to such borrowing adjusted for certain additional costs or (b) a base rate determined by reference to the highest of (1) the federal funds effective rate plus ½ of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate and (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable margin. The applicable margin ranges between .79% and 1.275% for eurocurrency rate borrowings and 0.0% and .275% for base rate borrowings, depending on the Parent Company’s debt ratings as of the date of determination.
Line of credit facility, amount outstanding \| ¥																						¥ 0
$100 million dollar line of credit
Debt Instrument [Line Items]
Line of credit facility term																		364 days
Line of credit facility, maximum borrowing capacity																		$ 100,000,000
Line of credit facility, interest rate description																		Borrowings will bear interest at the rate quoted by the bank and agreed upon at the time of making such loan and will have a three-month maturity period.
Line of credit facility, amount outstanding																		$ 0
$50 million dollar line of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity																		$ 50,000,000
Line of credit facility, interest rate description																		Borrowings will bear interest at the rate quoted by the bank and agreed upon at the time of making such loan and will have a three-month maturity period.
Line of credit facility, amount outstanding																		$ 0
Upper Limit \| 55 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage																		0.225%
Lower Limit \| 55 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage																		0.085%