Commitments and Contingencies Incurred But Not Reported Health Benefit Cost Accrual (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
IBNR Accrual	$ 2,511	$ 2,056

The accrued obligation as of the balance sheet date which represents the cost of settling insured claims and insured claims relating to insured events that have occurred but have not yet been reported to the insurer or reinsurer as of the date of the financial statements.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.W)

-URI http://asc.fasb.org/extlink&oid=6483420&loc=d3e570705-122907

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section W

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

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Balance Type:	credit
Period Type:	instant