CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS - FAIR VALUE (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair value hierarchy for financial assets and liabilities
Assets	$ 24,970	$ 89,574
Liabilities	1,613	14,825
Zipsor
Fair value hierarchy for financial assets and liabilities
Liabilities, contingent consideration	464	1,489
Lazanda
Fair value hierarchy for financial assets and liabilities
Liabilities, contingent consideration	156	11,742
CAMBIA
Fair value hierarchy for financial assets and liabilities
Liabilities, contingent consideration	993	1,594
Corporate debt securities
Fair value hierarchy for financial assets and liabilities
Assets	1,205	36,850
Money market funds
Fair value hierarchy for financial assets and liabilities
Assets	95	532
Commercial paper
Fair value hierarchy for financial assets and liabilities
Assets	23,670	52,192
Level 1
Fair value hierarchy for financial assets and liabilities
Assets	95	532
Level 1 \| Money market funds
Fair value hierarchy for financial assets and liabilities
Assets	95	532
Level 2
Fair value hierarchy for financial assets and liabilities
Assets	24,875	89,042
Level 2 \| Corporate debt securities
Fair value hierarchy for financial assets and liabilities
Assets	1,205	36,850
Level 2 \| Commercial paper
Fair value hierarchy for financial assets and liabilities
Assets	23,670	52,192
Level 3
Fair value hierarchy for financial assets and liabilities
Liabilities	1,613	14,825
Level 3 \| Zipsor
Fair value hierarchy for financial assets and liabilities
Liabilities, contingent consideration	464	1,489
Level 3 \| Lazanda
Fair value hierarchy for financial assets and liabilities
Liabilities, contingent consideration	156	11,742
Level 3 \| CAMBIA
Fair value hierarchy for financial assets and liabilities
Liabilities, contingent consideration	$ 993	$ 1,594

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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

- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

+ Details

Name:	us-gaap_BusinessCombinationContingentConsiderationLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=depo_XanodyneZipsorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=depo_ArchimedeLazandaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=depo_NautilusCAMBIAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CashAndCashEquivalentsAxis=us-gaap_MoneyMarketFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CashAndCashEquivalentsAxis=us-gaap_CommercialPaperMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: