Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested

No definition available.

Name:	omcl_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVested
Namespace Prefix:	omcl_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Share Based Compensation Arrangement by Share-based Payment, Determination of Performance Based Award

+ References

No definition available.

+ Details

Name:	omcl_ShareBasedCompensationArrangementbySharebasedPaymentDeterminationofPerformanceBasedAward
Namespace Prefix:	omcl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period, Number of Monthly Installments

+ References

No definition available.

+ Details

Name:	omcl_SharebasedCompensationArrangementbySharebasedPaymentAwardAwardVestingPeriodNumberofMonthlyInstallments
Namespace Prefix:	omcl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Eligible for Vesting

+ References

No definition available.

+ Details

Name:	omcl_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsEligibleforVesting
Namespace Prefix:	omcl_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Percent Eligible for Time-based Vesting

+ References

No definition available.

+ Details

Name:	omcl_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsPercentEligibleforTimebasedVesting
Namespace Prefix:	omcl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation, Arrangement by Share based Payment Award, Period Use to Calculate Rate of Return

+ References

No definition available.

+ Details

Name:	omcl_SharebasedCompensationArrangementbySharebasedPaymentAwardPeriodUsetoCalculateRateofReturn
Namespace Prefix:	omcl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Ratio of Reduction to Authorized Shares

+ References

No definition available.

+ Details

Name:	omcl_SharebasedCompensationArrangementbySharebasedPaymentAwardRatioofReductiontoAuthorizedShares
Namespace Prefix:	omcl_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Trading Days Number of trading days used to calculate the average closing price of common stock.

+ References

No definition available.

+ Details

Name:	omcl_SharebasedCompensationArrangementbySharebasedPaymentAwardTradingDays
Namespace Prefix:	omcl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate number of common shares reserved for future issuance.

+ 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 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=omcl_SharebasedCompensationAwardTrancheFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=omcl_TwoThousandNinePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=omcl_TwentyThirteenPerformanceBasedRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=omcl_A2014PerformanceBasedRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_OfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Employee Benefits and Share-Based Compensation - Stock Award Plans (Details)							1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 07, 2016 shares	Mar. 03, 2015 shares	Mar. 20, 2014	Dec. 16, 2010 shares	Oct. 01, 2010	May 19, 2009 shares	Dec. 31, 2014 Day	Dec. 31, 2013 shares	Dec. 31, 2016 mo shares	Dec. 31, 2015 shares	Dec. 31, 2014 shares	Dec. 31, 2013 shares	Dec. 31, 2012 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction to share available for issuance (in per share)				2.15
Increase to shares authorized (in shares)						2,600,000
Shares reserved for future issuance (in shares)									9,907,000
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period used to calculate annual rates of return									1 year
Trading days \| Day							20
Performance Shares \| Vesting years subsequent the date of grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									3 years
Awards eligible for vesting (in shares)	60,000
Awards vested by period end (in shares)									30,000
2009 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance				2,600,000.0
Reduction to share available for issuance (in per share)				1.8	1.4				1
Increase to shares authorized (in shares)									3,200,000			2,500,000
Shares reserved for future issuance (in shares)									7,076,000
2009 Plan \| Vesting one year from the vesting commencement date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of award vesting									25.00%
2009 Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									4 years
Shares reserved for future issuance (in shares)									3,214,000
2009 Plan \| Employee Stock Option \| Vesting one year from the vesting commencement date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									1 year
2009 Plan \| Employee Stock Option \| Vesting in equal monthly installments
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Monthly vesting installments \| mo									36
2009 Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									4 years
Shares reserved for future issuance (in shares)									719,000
Shares granted (in shares)									289,000
Vested (in shares)									179,000
2009 Plan \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)									123,000
Vested (in shares)									90,000
2013 Performance Based Restricted Stock Units \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares eligible for time-based vesting			100.00%
2013 Performance Based Restricted Stock Units \| Performance Shares \| Vested immediately
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of award vesting			25.00%
2014 Performance Based Restricted Stock Units \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards eligible for vesting (in shares)		132,500
Awards vested by period end (in shares)									93,000
Percentile rank of stockholder return	66.00%	74.40%
Officer \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)								137,500	122,740	60,000	132,500		125,000
Awards eligible for vesting (in shares)													62,500