Valuation and Qualifying Accounts (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation and Qualifying Accounts Disclosure [Line Items]
Provision For Doubtful Accounts	$ 16,461,000	$ 21,728,000	$ 13,708,000
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance, Beginning Balance	21,000,000	17,400,000	21,000,000
Provision For Doubtful Accounts	16,400,000	21,700,000	13,700,000
Write-Offs	(23,200,000)	(18,100,000)	(17,300,000)
Valuation Allowances and Reserves, Balance, Ending Balance	14,200,000	21,000,000	17,400,000
Allowance for Doubtful Accounts - Discontinued Operations [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Provision For Doubtful Accounts	600,000	700,000	1,100,000
Estimated Revenue Adjustments [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance, Beginning Balance	6,400,000	6,800,000	6,500,000
Provision for Estimated Revenue Adjustments	9,400,000	10,600,000	12,100,000
Write-Offs	(11,900,000)	(11,000,000)	(11,800,000)
Valuation Allowances and Reserves, Balance, Ending Balance	3,900,000	6,400,000	6,800,000
Estimated Revenue Adjustments, Discontinued Operations [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Provision for Estimated Revenue Adjustments	$ 400,000	$ 700,000	$ 1,200,000