Acquisitions And Other Investments - BLS (Schedule Of Business Acquisitions, Consideration Paid And Purchase Price Allocation) (Detail) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011	Dec. 02, 2012 Bottom Line Services [Member]	Dec. 02, 2012 Bottom Line Services [Member] Trade Names [Member]	Dec. 02, 2012 Bottom Line Services [Member] Noncompete Agreements [Member]	Dec. 02, 2012 Bottom Line Services [Member] Customer Relationships [Member]	Dec. 02, 2012 Bottom Line Services [Member] Other Current Assets [Member]	Dec. 02, 2012 Bottom Line Services [Member] Accrued Liabilities [Member]	Dec. 02, 2012 Bottom Line Services [Member] Earn-out Arrangements [Member]
Purchase price consideration:
Cash					$ 67,600,000
Fair value of contingent consideration (earn-out liability)											11,100,000
Total consideration transferred					78,700,000
Purchase price allocation to identifiable assets acquired and liabilities assumed:
Assets									36,400,000
Property and equipment					12,600,000
Intangible assets						2,600,000	500,000	24,400,000
Liabilities										(10,400,000)
Total identifiable net assets					66,100,000
Goodwill	824,014,000	824,707,000	714,800,000	714,800,000	12,600,000
Total consideration allocated					$ 78,700,000