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Represents the ratio between the liquid assets and the liabilities of an entity under the terms of debt instrument.

No definition available.

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The percentage of prepayment fee under debt agreement.

No definition available.

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Represents the number of consecutive calendar quarters to maintain threshold limit of EDITDA to repay principal and interest prior to specific date.

No definition available.

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Represents the threshold limit of EDITDA to repay principal and interest prior to specific date.

No definition available.

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

No definition available.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

No definition available.

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

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=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of the fee that accompanies borrowing money under the debt instrument.

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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.

No definition available.

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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.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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Data Type:	num:percentItemType
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Period Type:	instant

Amount of cash inflow (outflow) from long-term debt supported by a written promise to pay an obligation.

No definition available.

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Number of new stock issued during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Data Type:	xbrli:sharesItemType
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_NotesPayableToBanksMember
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Name:	us-gaap_DebtInstrumentAxis=coll_SiliconValleyBankLoanAgreement28August2012Member
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Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
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Name:	us-gaap_LongtermDebtTypeAxis=coll_NewTermLoanFacilityMember
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