Annual capital expenditure limitation per Credit Agreement

No definition available.

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Period Type:	instant

- Definition

Line of Credit Facility, Periodic Payment, Principal, Percent, Year Five

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Periodic Payment, Principal, Percent, Years One And Two

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Periodic Payment, Principal, Percent, Years Three And Four

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Long-term Line of Credit, Gross

+ References

No definition available.

+ Details

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Namespace Prefix:	omcl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum allowed non-permitted investments per Credit Agreement

+ References

No definition available.

+ Details

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Namespace Prefix:	omcl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
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

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

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
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+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
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Debt and Credit Agreements - Narrative (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jan. 05, 2016	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 26, 2017	Apr. 11, 2017
Debt Instrument [Line Items]
Repayment of debt and revolving credit facility				$ 60,000,000	$ 12,500,000
Interest expense		$ 900,000	$ 1,900,000	2,200,000	3,800,000
Amortization of debt financing fees		600,000	$ 600,000	1,145,000	$ 1,145,000
Wells Fargo Bank, National Association
Debt Instrument [Line Items]
Proceeds from lines of credit				0
Repayment of debt and revolving credit facility				60,000,000.0
Amortization of debt financing fees				1,145,000
Carrying amount of debt		80,000,000.0		80,000,000.0		$ 140,000,000
Fair value of debt		80,200,000		80,200,000
Wells Fargo Bank, National Association \| Secured Debt \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 400,000,000.0
Annual capital expenditure limitation per Credit Agreement	35,000,000.0							$ 45,000,000.0
Maximum allowed non-permitted investments per Credit Agreement	10,000,000.0							$ 20,000,000.0
Deferred issuance cost, gross	$ 10,100,000
Wells Fargo Bank, National Association \| Secured Debt \| Line of Credit \| Credit Agreement, Interest Rate Option One \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Wells Fargo Bank, National Association \| Secured Debt \| Line of Credit \| Credit Agreement, Interest Rate Option One \| London Interbank Offered Rate (LIBOR) \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Wells Fargo Bank, National Association \| Secured Debt \| Line of Credit \| Credit Agreement, Interest Rate Option Two \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Wells Fargo Bank, National Association \| Secured Debt \| Line of Credit \| Credit Agreement, Interest Rate Option Two \| London Interbank Offered Rate (LIBOR) \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Wells Fargo Bank, National Association \| Secured Debt \| Line of Credit \| Credit Agreement, Interest Rate Option Two \| Federal Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Wells Fargo Bank, National Association \| Revolving credit facility
Debt Instrument [Line Items]
Proceeds from lines of credit				0
Repayment of debt and revolving credit facility				0
Carrying amount of debt		0		0		0
Wells Fargo Bank, National Association \| Revolving credit facility \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 200,000,000.0						$ 315,000,000.0
Debt instrument, term (in years)	5 years
Wells Fargo Bank, National Association \| Revolving credit facility \| Line of Credit \| Minimum
Debt Instrument [Line Items]
Commitment fee, percentage	0.20%
Wells Fargo Bank, National Association \| Revolving credit facility \| Line of Credit \| Maximum
Debt Instrument [Line Items]
Commitment fee, percentage	0.35%
Wells Fargo Bank, National Association \| Term loan facility
Debt Instrument [Line Items]
Proceeds from lines of credit				0
Repayment of debt and revolving credit facility				60,000,000
Carrying amount of debt		$ 80,000,000		$ 80,000,000		$ 140,000,000
Wells Fargo Bank, National Association \| Term loan facility \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 200,000,000.0
Debt instrument, term (in years)	5 years
Principal periodic payment, percent, years one and two	5.00%
Principal periodic payment, percent, years three and four	10.00%
Principal periodic payment, percent, year five	15.00%
Wells Fargo Bank, National Association \| Letter of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 10,000,000.0
Wells Fargo Bank, National Association \| Letter of Credit \| Line of Credit \| Minimum
Debt Instrument [Line Items]
Participation fee, percentage	1.50%
Wells Fargo Bank, National Association \| Letter of Credit \| Line of Credit \| Maximum
Debt Instrument [Line Items]
Participation fee, percentage	2.25%
Wells Fargo Bank, National Association \| Swing line loan, Sub-limit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 10,000,000.0