Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for Doubtful Accounts
Changes in valuation and qualifying accounts
Balance at Beginning of Year	$ 47,469	$ 44,416	$ 43,357
Charged to Cost and Expenses	39,055	51,347	41,147
Acquisitions		108	7,448
Deductions	(44,670)	(48,402)	(47,536)
Balance at End of Year	41,854	47,469	44,416
Income Tax Valuation Allowance
Changes in valuation and qualifying accounts
Balance at Beginning of Year	15,733	16,622	22,372
Charged to Cost and Expenses	(2,392)	(889)	(5,750)
Balance at End of Year	$ 13,341	$ 15,733	$ 16,622

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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- Definition

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