Acquisitions - Additional Information (Detail) (USD $) Share data in Millions, unless otherwise specified	12 Months Ended			0 Months Ended	12 Months Ended			1 Months Ended	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Nov. 01, 2012 Phoenix	Dec. 31, 2012 Phoenix	Dec. 31, 2011 Phoenix	Oct. 02, 2012 Apreo	Sep. 30, 2011 Timco Worldwide	Dec. 31, 2012 T-Chek	Oct. 16, 2012 T-Chek
Business Acquisition [Line Items]
Business acquisition, purchase price				$ 660,576,000
Business acquisition, equity interest issued or issuable, value assigned				60,200,000
Business acquisition, equity interest issued or issuable, number of shares				1.1
Business acquisition, acquisition price financed with debt				173,000,000
Business acquisition, cost of acquired entity, transaction costs				9,900,000
Business acquisition, pro forma revenue					12,100,000,000	11,200,000,000
Business acquisition, pro forma operating income					707,400,000	729,600,000
Business acquisition, pro forma net income					610,700,000	445,800,000
Business acquisition, pro forma amortization expense					13,600,000	16,300,000
Business acquisition, pro forma interest expense					2,200,000	2,600,000
Business acquisition, pro forma professional fees					18,500,000
Business acquisition, pro forma compensation related expenses					6,500,000	4,100,000
Business acquisition, pro forma consolidated effective tax rate					6,900,000	1,800,000
Long lived assets held-for-sale, proceeds from sale										302,500,000
Gain on sale of T-Chek	281,551,000	0	0						281,600,000
Business acquisition, cash paid							26,500,000
Business acquisition, goodwill and other intangible assets							17,400,000	2,400,000
Business acquisition, liabilities assumed								$ 3,800,000
Business acquisition, goodwill and other intangible assets tax deductible term								15 years