v2.4.1.9

Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Unrecognized Tax Benefits	$ 4us-gaap_UnrecognizedTaxBenefits	$ 3us-gaap_UnrecognizedTaxBenefits
Federal and state net operating losses acquired in business combinations	5cnc_NetOperatingLossesAcquiredInBusinessCombinations
Valuation allowance additions in the tax provision	5cnc_ValuationAllowanceAdditions	1cnc_ValuationAllowanceAdditions
Valuation allowance reductions	1cnc_ValuationAllowanceReductions	1cnc_ValuationAllowanceReductions
Tax Benefit Related to 2013	$ 14cnc_TaxBenefitRelatedto2013
Minimum [Member]
Income Taxes [Line Items]
Federal Net Operating Losses Expire Period	2020
State Net Operating Losses Expire Period	2015
Maximum [Member]
Income Taxes [Line Items]
Federal Net Operating Losses Expire Period	2033
State Net Operating Losses Expire Period	2035

X

- Definition

Federal net operating losses expire period.

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- Details

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- Definition

Net Operating Losses Acquired In Business Combinations

+ References

No definition available.

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- Definition

State net operating losses expire period.

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- Definition

Tax benefit recognized for new regulations on compensation deduction limitation in 2013 and 2014, related to 2013.

+ References

No definition available.

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- Definition

Valuation allowance additions.

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- Definition

Valuation allowance reductions.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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