Valuation and Qualifying Accounts (Details) (Allowance for Doubtful Accounts [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Allowance for Doubtful Accounts, Balance at beginning of year	$ 54,238		$ 48,125		$ 37,998
Allowance for doubtful accounts, Charged to Income	9,201		12,452		12,957
Allowance for Doubtful Accounts, Other	8,098	[1]	3,262	[1]	5,357	[1]
Allowance for Doubtful Accounts, Write-down	7,408		9,601		8,187
Allowance for Doubtful Accounts, Balance at end of year	$ 64,129		$ 54,238		$ 48,125

[1] Represents the allowance for doubtful accounts of the businesses acquired by the company during 2013, 2012, and 2011.