Debt Instrument, Convertible, Discount Amortization Period

No definition available.

Name:	moh_DebtInstrumentConvertibleDiscountAmortizationPeriod
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Convertible, Maximum Threshold Percentage of Stock Price Trigger

+ References

No definition available.

+ Details

Name:	moh_DebtInstrumentConvertibleMaximumThresholdPercentageofStockPriceTrigger
Namespace Prefix:	moh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Additional interest rate per year to be payable for any semiannual interest period for which principal amount outstanding on Notes is less than the required amount

+ References

No definition available.

+ Details

Name:	moh_DebtInstrumentInterestRateIncreaseContingentonPrincipalAmountOutstanding
Namespace Prefix:	moh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Interest Rate Increase, Minimum Principal Amount Outstanding Threshold

+ References

No definition available.

+ Details

Name:	moh_DebtInstrumentInterestRateIncreaseMinimumPrincipalAmountOutstandingThreshold
Namespace Prefix:	moh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Potential Maximum Borrowing Capacity

+ References

No definition available.

+ Details

Name:	moh_LineofCreditFacilityPotentialMaximumBorrowingCapacity
Namespace Prefix:	moh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

+ References

+ Details

Name:	us-gaap_ConvertibleDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031897-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Conversion Rate
-URI http://asc.fasb.org/extlink&oid=6509012

Reference 3: 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(a)(5))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentFrequencyOfPeriodicPayment
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Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

End date of debt instrument redemption period, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Start date of debt instrument redemption period, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Period Type:	duration

- References

No definition available.

+ Details

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Period Type:	duration

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of when the fee for available but unused credit capacity is required to be paid (for example, annually, quarterly, or monthly).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityFrequencyOfCommitmentFeePayment
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current portion 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_LongtermConvertibleDebtCurrentAndNoncurrentAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConvertibleDebtMember
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Period Type:

- Details

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Debt (Details)			1 Months Ended			6 Months Ended	12 Months Ended
Debt (Details)	Nov. 10, 2015 USD ($)	Jun. 12, 2015 USD ($)	Sep. 30, 2014 USD ($) d $ / shares	Aug. 30, 2014 USD ($)	Feb. 28, 2013 USD ($) d $ / shares	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($) $ / shares	Dec. 31, 2014 USD ($)	Jun. 30, 2015 USD ($)
5.375% Notes
Debt Instrument [Line Items]
Percentage of contractual interest rate on Notes						5.375%	5.375%
1.625% Notes
Debt Instrument [Line Items]
Percentage of contractual interest rate on Notes						1.625%	1.625%
1.125% Convertible Notes
Debt Instrument [Line Items]
Percentage of contractual interest rate on Notes						1.125%	1.125%
Convertible Debt [Abstract]
Senior note effective interest rate (in percent)							6.00%
Senior notes amortization period							4 years
Convertible debt, if-converted value in excess of principal							$ 332,000,000	$ 93,000,000
Senior Notes \| 5.375% Notes
Debt Instrument [Line Items]
Face amount of debts	$ 700,000,000
Percentage of contractual interest rate on Notes	5.375%
Senior Notes [Abstract]
Debt redemption price, percentage of principal amount	100.00%
Senior Notes \| 1.125% Convertible Notes
Debt Instrument [Line Items]
Face amount of debts					$ 550,000,000
Percentage of contractual interest rate on Notes					1.125%
Convertible Debt [Abstract]
Initial conversation rate on Notes					0.0245277
Conversion price per share of common stock \| $ / shares					$ 40.77
Long-term portion of convertible debt.						$ 460,000,000
Senior note effective interest rate (in percent)						6.00%
Senior notes amortization period						3 years 6 months
Convertible debt, if-converted value in excess of principal						$ 180,000,000	$ 332,000,000
Convertible Debt \| 1.625% Notes
Debt Instrument [Line Items]
Face amount of debts			$ 301,551,000.000
Percentage of contractual interest rate on Notes			1.625%
Term of debt instrument			4 years
Convertible Debt [Abstract]
Initial conversation rate on Notes			0.0172157
Conversion price per share of common stock \| $ / shares			$ 58.09				$ 58.09
Senior note effective interest rate (in percent)						5.00%	5.00%
Convertible debt, if-converted value in excess of principal							$ 10,000,000
Proceeds from issuance of debt			$ 125,000,000.0	$ 177,000,000
Extinguishment of Debt Disclosures [Abstract]
Frequency of periodic payment						semiannually	semiannually
Additional interest payable for any semiannual interest period with 1.625% Notes outstanding less than $100 million			0.25%
Minimum 1.625% Notes outstanding balance threshold for additional interest payable						$ 100,000,000	$ 100,000,000
Senior Notes [Abstract]
Redemption period start date						Aug. 19, 2018	Aug. 19, 2018
Debt redemption price, percentage of principal amount						100.00%	100.00%
Debt discount amortization period						2 years 1 month	2 years 7 months
Convertible debt, carrying amount of equity component						$ 23,000,000	$ 23,000,000
Redemption period, option one \| Senior Notes \| 1.625% Notes
Convertible Debt [Abstract]
Debt convertible threshold trading days \| d			20
Debt convertible threshold consecutive trading days			30 days
Debt convertible threshold percentage of stock price trigger			130.00%
Redemption period, option one \| Senior Notes \| 1.125% Convertible Notes
Convertible Debt [Abstract]
Debt convertible threshold trading days \| d					20
Debt convertible threshold consecutive trading days					30 days
Debt convertible threshold percentage of stock price trigger					130.00%
Redemption period, option one \| Convertible Debt \| 1.625% Notes
Convertible Debt [Abstract]
Debt convertible threshold trading days \| d			20
Debt convertible threshold consecutive trading days			30 days
Debt convertible threshold percentage of stock price trigger			130.00%
Redemption period, option two \| Senior Notes \| 1.625% Notes
Convertible Debt [Abstract]
Debt convertible threshold trading days \| d			5
Debt convertible threshold consecutive trading days			5 days
Debt convertible maximum threshold percentage of stock price			98.00%
Redemption period, option two \| Senior Notes \| 1.125% Convertible Notes
Convertible Debt [Abstract]
Debt convertible threshold trading days \| d					5
Debt convertible threshold consecutive trading days					5 days
Debt convertible maximum threshold percentage of stock price					98.00%
Redemption period, option two \| Convertible Debt \| 1.625% Notes
Convertible Debt [Abstract]
Debt convertible threshold trading days \| d			5
Debt convertible threshold consecutive trading days			5 days
Debt convertible maximum threshold percentage of stock price			98.00%
August 19, 2018 \| Convertible Debt \| 1.625% Notes
Senior Notes [Abstract]
Redemption period start date						Aug. 19, 2018	Aug. 19, 2018
Redemption period end date						Aug. 19, 2018
August 19, 2024 \| Convertible Debt \| 1.625% Notes
Senior Notes [Abstract]
Redemption period start date						Aug. 19, 2024	Aug. 19, 2024
Redemption period end date						Aug. 19, 2024
August 19, 2029 \| Convertible Debt \| 1.625% Notes
Senior Notes [Abstract]
Redemption period start date						Aug. 19, 2029	Aug. 19, 2029
Redemption period end date						Aug. 19, 2029
August 19, 2034 \| Convertible Debt \| 1.625% Notes
Senior Notes [Abstract]
Redemption period start date						Aug. 19, 2034	Aug. 19, 2034
Redemption period end date						Aug. 19, 2034
August 19, 2039 \| Convertible Debt \| 1.625% Notes
Senior Notes [Abstract]
Redemption period start date						Aug. 19, 2039	Aug. 19, 2039
Redemption period end date						Aug. 19, 2039
Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity									$ 250,000,000
Term of debt instrument		5 years
Potential maximum borrowing capacity		$ 350,000,000							$ 350,000,000
Current borrowing capacity						$ 244,000,000	$ 244,000,000
Amount outstanding under the Credit Facility						$ 0	$ 0
Frequency of commitment fee payment						quarterly	quarterly
Letter of Credit
Debt Instrument [Line Items]
Amount outstanding under Letter of Credit						$ 6,000,000	$ 6,000,000