v2.4.0.8

Organization and Summary of Significant Accounting Policies Accounts Receivable Concentration (Details)	Sep. 30, 2013 customer	Dec. 31, 2012 customer
Concentration Risk [Line Items]
customers with 10 % accts rec concentration	0	0

X

- Definition

customers with 10 % accts rec concentration = number of customers with greater than or equal to 10% of Accts Receivable for the reported balance sheet date

+ References

No definition available.

+ Details

Name:	omcl_CustomersWith10AcctsRecConcentration
Namespace Prefix:	omcl_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

X

- Details

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