Fair Value Measurements - Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) (USD $)	Aug. 31, 2014	May 31, 2014	Aug. 31, 2013
Liabilities:
Fair value of long-term debt	$ 5,897,000,000	$ 5,912,900,000
Carrying value of long-term debt	5,736,300,000	5,720,400,000
Fair value of assets measured on a nonrecurring basis	0		0
Fair value of liabilities measured on a nonrecurring basis	0		0
Recurring [Member]
Assets:
Total assets, Fair Value	267,300,000	319,900,000
Liabilities:
Total liabilities, Fair Value	18,200,000	21,500,000
Recurring [Member] | Money market funds [Member]
Assets:
Total assets, Fair Value	88,700,000	145,000,000
Recurring [Member] | Time deposit [Member]
Assets:
Total assets, Fair Value	24,900,000	25,800,000
Recurring [Member] | Pension plan assets [Member]
Assets:
Total assets, Fair Value	147,400,000	147,500,000
Recurring [Member] | Foreign currency exchange contracts [Member]
Assets:
Total assets, Fair Value	3,000,000	1,100,000
Liabilities:
Total liabilities, Fair Value	3,400,000	1,300,000
Recurring [Member] | Equity securities [Member]
Assets:
Total assets, Fair Value	3,300,000	500,000
Recurring [Member] | Interest rate swaps [Member]
Liabilities:
Total liabilities, Fair Value	14,800,000	20,200,000
Recurring [Member] | Level 1 [Member]
Assets:
Total assets, Fair Value	91,800,000	145,300,000
Liabilities:
Total liabilities, Fair Value	0	0
Recurring [Member] | Level 1 [Member] | Money market funds [Member]
Assets:
Total assets, Fair Value	88,700,000	145,000,000
Recurring [Member] | Level 1 [Member] | Time deposit [Member]
Assets:
Total assets, Fair Value	0	0
Recurring [Member] | Level 1 [Member] | Pension plan assets [Member]
Assets:
Total assets, Fair Value	0	0
Recurring [Member] | Level 1 [Member] | Foreign currency exchange contracts [Member]
Assets:
Total assets, Fair Value	0	0
Liabilities:
Total liabilities, Fair Value	0	0
Recurring [Member] | Level 1 [Member] | Equity securities [Member]
Assets:
Total assets, Fair Value	3,100,000	300,000
Recurring [Member] | Level 1 [Member] | Interest rate swaps [Member]
Liabilities:
Total liabilities, Fair Value	0	0
Recurring [Member] | Level 2 [Member]
Assets:
Total assets, Fair Value	160,300,000	159,400,000
Liabilities:
Total liabilities, Fair Value	18,200,000	21,500,000
Recurring [Member] | Level 2 [Member] | Money market funds [Member]
Assets:
Total assets, Fair Value	0	0
Recurring [Member] | Level 2 [Member] | Time deposit [Member]
Assets:
Total assets, Fair Value	24,900,000	25,800,000
Recurring [Member] | Level 2 [Member] | Pension plan assets [Member]
Assets:
Total assets, Fair Value	132,400,000	132,500,000
Recurring [Member] | Level 2 [Member] | Foreign currency exchange contracts [Member]
Assets:
Total assets, Fair Value	3,000,000	1,100,000
Liabilities:
Total liabilities, Fair Value	3,400,000	1,300,000
Recurring [Member] | Level 2 [Member] | Equity securities [Member]
Assets:
Total assets, Fair Value	0	0
Recurring [Member] | Level 2 [Member] | Interest rate swaps [Member]
Liabilities:
Total liabilities, Fair Value	14,800,000	20,200,000
Recurring [Member] | Level 3 [Member]
Assets:
Total assets, Fair Value	15,200,000	15,200,000
Liabilities:
Total liabilities, Fair Value	0	0
Recurring [Member] | Level 3 [Member] | Money market funds [Member]
Assets:
Total assets, Fair Value	0	0
Recurring [Member] | Level 3 [Member] | Time deposit [Member]
Assets:
Total assets, Fair Value	0	0
Recurring [Member] | Level 3 [Member] | Pension plan assets [Member]
Assets:
Total assets, Fair Value	15,000,000	15,000,000
Recurring [Member] | Level 3 [Member] | Foreign currency exchange contracts [Member]
Assets:
Total assets, Fair Value	0	0
Liabilities:
Total liabilities, Fair Value	0	0
Recurring [Member] | Level 3 [Member] | Equity securities [Member]
Assets:
Total assets, Fair Value	200,000	200,000
Recurring [Member] | Level 3 [Member] | Interest rate swaps [Member]
Liabilities:
Total liabilities, Fair Value	$ 0	$ 0