Amount of dividends paid to our parent company without prior approval by state regulatory authorities

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- Definition

Statutory Accounting Practices, Statutory Capital and Surplus Required, Contributions

+ References

No definition available.

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- Definition

This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50% or less owned persons accounted for using the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(b))
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.9-06)
-URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537971-122884

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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.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

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No definition available.

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Subparagraph (SX 210.9-03(16))
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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Period Type:	instant

- Definition

Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due after 1 year (or 1 business cycle).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
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-Paragraph 1
-Subparagraph (SX 210.5-02(11))
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Period Type:	instant

- Definition

Amount of dividends that can be declared or paid without approval of regulatory agency.

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Balance Type:	credit
Period Type:	instant

- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
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- Definition

Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 505
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-Paragraph 1
-Subparagraph (b)
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(Additional Information) (Detail) - USD ($)	3 Months Ended	12 Months Ended
(Additional Information) (Detail) - USD ($)	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Outstanding borrowings, line of credit		$ 0
Investment income		405,000,000	$ 389,000,000	$ 474,000,000
Cash dividends received from subsidiary		1,400,000,000	763,000,000	493,000,000
Aggregate statutory capital and surplus in our state regulated insurance subsidiaries		8,000,000,000	7,700,000,000
Aggregate minimum regulatory requirements of statutory capital and surplus		4,800,000,000	4,800,000,000
Dividends that may be paid to the parent company without prior approval by state regulatory authorities in 2014		1,100,000,000
Dividends that were paid to the parent company without prior approval by state regulatory authorities		1,400,000,000
Contributions of statutory capital and surplus into regulated subsidiaries (in first quarter of 2016)	$ 535,000,000
MCCI
Condensed Financial Statements, Captions [Line Items]
Maximum borrowing capacity		55,000,000
Outstanding borrowings, line of credit		18,000,000	0
Majority-Owned Subsidiary, Unconsolidated
Condensed Financial Statements, Captions [Line Items]
Interest expense on subsidiary notes payable		1,000,000	1,000,000	1,000,000
Other long-term assets \| MCCI
Condensed Financial Statements, Captions [Line Items]
Related party receivable		$ 349,000,000	314,000,000
Minimum \| Majority-Owned Subsidiary, Unconsolidated
Condensed Financial Statements, Captions [Line Items]
Debt instrument, stated interest rate		2.14%
Maximum \| Majority-Owned Subsidiary, Unconsolidated
Condensed Financial Statements, Captions [Line Items]
Debt instrument, stated interest rate		6.65%
Healthcare Services \| Operating Segments
Condensed Financial Statements, Captions [Line Items]
Investment income		$ 35,000,000	$ 30,000,000	$ 0