Total of premiums and other receivables, net and reinsurance recoverables.

No definition available.

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- Definition

For an entity that discloses a concentration risk as a percentage of some financial balance or benchmark, this item identifies a second characteristic of the concentration. For example, "Europe" is the second characteristic in the phrase: "net assets in Europe are 70% of total net assets".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Topic 275
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-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

+ Details

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- Definition

Identifies or describes the benchmark that serves as the denominator in the calculation of the percentage of concentration risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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- Details

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- Details

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- Details

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Segment Information - Concentration Risk (Details) - USD ($) $ in Billions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Revenue Consolidated [Member] \| Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	18.00%	18.00%
Concentration Risk, Benchmark Description	Consolidated revenues
Concentration Risk, Additional Characteristic	Premiums and fees from CMS
CMS [Member]
Concentration Risk [Line Items]
Net receivables from CMS	$ 0.3		$ 0.5