Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts and Bilinig Adjustments
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 3,970	$ 2,777	$ 2,175
Provisions	1,787	(166)	1,127
Deductions	(2,690)	1,359	(525)
Balance at end of year	3,067	3,970	2,777
Allowance for Workers' Compensation and Medical Malpractice Loss Reserves
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	26,769	27,003	28,244
Provisions	5,956	3,594	2,339
Deductions	26	(3,828)	(3,580)
Balance at end of year	$ 32,751	$ 26,769	$ 27,003

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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

+ References

+ Details

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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.

+ References

+ Details

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