Debt - Additional Information (Detail)	12 Months Ended								12 Months Ended			12 Months Ended					12 Months Ended		12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2014 Senior Credit Facility [Member]	Dec. 31, 2014 Prior Term Loan [Member] Ratio	Dec. 31, 2014 After Term Loan [Member] Ratio	Dec. 31, 2014 Term Loan [Member] Senior Credit Facility [Member]	May 31, 2014 Term Loan [Member] Senior Credit Facility [Member] USD ($)	Dec. 31, 2014 Multicurrency Revolving Facility [Member]	Dec. 31, 2014 Multicurrency Revolving Facility [Member] Senior Credit Facility [Member]	May 31, 2014 Multicurrency Revolving Facility [Member] Senior Credit Facility [Member] USD ($)	Dec. 31, 2014 Bridge Credit Agreement [Member] USD ($)	Dec. 31, 2014 Japan Term Loan [Member] USD ($)	Dec. 31, 2014 Japan Term Loan [Member] JPY (¥)	Dec. 31, 2014 Senior Notes Due 2019 [Member] USD ($)	Dec. 31, 2013 Senior Notes Due 2019 [Member] USD ($)	Dec. 31, 2014 Senior Notes Due 2021 [Member] USD ($)	Dec. 31, 2013 Senior Notes Due 2021 [Member] USD ($)	Dec. 31, 2014 Senior Notes Due 2039 [Member] USD ($)	Dec. 31, 2013 Senior Notes Due 2039 [Member] USD ($)
Debt Instrument [Line Items]
Unsecured term loan, term							5 years			5 years		364 days
Principal amount, term loan description				The Senior Credit Facility contains (i) a 5-year unsecured term loan facility in the principal amount of $3.0 billion (Term Loan)								The Bridge Credit Agreement is a 364-day unsecured committed bridge facility in the principal amount of $7.66 billion.
Principal amount, unsecured credit facility											$ 1,350,000,000	$ 7,660,000,000
Credit facility, maturity date				May 31, 2017						May 31, 2019		Apr. 24, 2015
Principal amount, unsecured credit facility								3,000,000,000
Outstanding Senior Credit Facility	0
Term Loan	98,000,000	112,400,000												11,700,000,000
Interest rate on Senior Notes and term loan													0.61%	0.61%	4.625%		3.375%		5.75%
Due date of senior notes													May 31, 2018	May 31, 2018	Nov. 30, 2019		Nov. 30, 2021		Nov. 30, 2039
Estimated fair value of senior notes and term loan	1,460,200,000												97,600,000
Maximum Leverage Ratio					3.0	5.0
Leverage ratio description under line of credit facility on financial covenants				Financial covenants include a consolidated indebtedness to consolidated EBITDA ratio of no greater than 3.0 to 1.0 in periods prior to any Term Loan funding and no greater than 5.0 to 1.0 in periods after the Term Loan is funded.
Debt issuance costs commitment period									5 years			1 year
Aggregate Principal Amount of Senior Notes															500,000,000	500,000,000	300,000,000	300,000,000	500,000,000	500,000,000
Interest payable	Interest on each series is payable on May 30 and November 30 of each year until maturity.
Debt instruments redemption terms	Redemption price equal to the greater of 1) 100 percent of the principal amount of the notes being redeemed; or 2) the sum of the present values of the remaining scheduled payments of principal and interest (not including any portion of such payments of interest accrued as of the date of redemption), discounted to the date of redemption on a semi-annual basis at the Treasury Rate (as defined in the debt agreement), plus 20 basis points in the case of the 2019 Notes and 2021 Notes, and 25 basis points in the case of the 2039 Notes. We would also pay the accrued and unpaid interest on the Senior Notes to the redemption date.
Available uncommitted credit facilities, Net	31,900,000
Weighted average interest rate for all borrowings, long-term debt	3.50%	3.30%
Interest paid on Debt	$ 67,500,000	$ 68,100,000	$ 67,800,000