Goodwill And Other Intangible Assets (Rollforward of Intangible Assets, Including Goodwill) (Detail) (USD $)	6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012
Goodwill and Other Intangible Assets [Roll Forward]
Goodwill, beginning balance	$ 826,110,000		$ 714,800,000
Additions from new business combinations, goodwill	36,800,000
Currency translation adjustments, goodwill	(2,700,000)
Goodwill, ending balance	860,207,000		718,300,000
Other intangible assets, non-amortizing, beginning balance	66,200,000		66,200,000
Additions from new business combinations, non-amortizing intangible assets	29,600,000
Currency translation adjustments, non-amortizing intangible assets	(1,300,000)
Other intangible assets, non-amortizing, ending balance	94,500,000		66,200,000
Other intangible assets, amortizing, beginning balance	70,900,000	[1]	44,500,000
Additions from new business combinations, amortizing intangible assets	13,200,000
Amortization expense	(9,400,000)		(5,700,000)
Currency translation adjustments, amortizing intangible assets	(500,000)
Other intangible assets, amortizing, ending balance	74,200,000	[1]	38,800,000
Goodwill and other intangible assets, beginning balance	963,210,000		825,500,000
Goodwill and other intangible assets acquired	79,600,000
Goodwill and other intangible assets, translation adjustments	(4,500,000)
Goodwill and other intangible assets, ending balance	1,028,908,000		823,300,000
Earn-out Arrangements [Member]
Goodwill and Other Intangible Assets [Roll Forward]
Accruals of acquisition-related contingent consideration	$ 0	[2]	$ 3,500,000	[2]

[1] Consists principally of customer relationships, backlog, trade names and non-compete agreements with finite lives.

[2] Represents contingent consideration for acquisitions prior to January 1, 2009, which is only accrued as earned, in accordance with U.S. GAAP.