Liability for Unpaid Health Claims - Summary of Liability for Unpaid Health Claims (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Insurance [Abstract]
Balance at beginning of year	$ 101,719	$ 104,870	$ 103,517
Acquisition of Family Heritage	0	0	11,700
Incurred related to Current year	792,740	720,490	704,934
Incurred related to Prior years	(23,106)	(11,594)	(17,531)
Total incurred	769,634	708,896	687,403
Paid related to Current year	725,386	636,150	627,495
Paid related to Prior years	59,714	75,897	70,255
Total paid	785,100	712,047	697,750
Balance at end of year	$ 86,253	$ 101,719	$ 104,870

Amount of expense in the period for claims incurred in current reporting period.

No definition available.

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- Definition

Amount of expense in the period for claims incurred in prior reporting periods.

+ References

No definition available.

+ Details

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- Definition

Liability For Unpaid Claims Assumed Due To Acquisition Of Subsidiary

+ References

No definition available.

+ Details

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- Definition

Amount of payments made during the reporting period to settle insured claims.

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No definition available.

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- Details

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- Definition

Amount of payments to settle claims incurred in the current period and related claims settlement costs.

+ References

+ Details

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- Definition

Amount of payments to settle claims incurred in prior periods and related claims settlement costs.

+ References

+ Details

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- Definition

Amount of expense for claims incurred and costs incurred in the claim settlement process.

+ References

+ Details

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- Definition

Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

+ References

Reference 1: 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

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

-Publisher SEC

-Name Financial Reporting Release (FRR)

-Number 403

-Paragraph 04

-Subparagraph b

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph a

-Article 7

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