XML 65 R42.htm IDEA: XBRL DOCUMENT
v3.20.2

Revenue Recognition - Summarize Activity of the Net Product Revenue Allowance and Reserve Categories (Detail) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2020 | Sep. 30, 2019
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Beginning balance | $ 128,557 | $ 65,244
Provision related to current period sales | 585,206 | 369,133
Provision related to prior period sales | (3,872) | (204)
Credits/payments made for current period sales | (384,035) | (249,600)
Credits/payments made for prior period sales | (118,742) | (62,540)
Ending balance | 207,114 | 122,033
Trade Allowances |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Beginning balance | 29,261 | 19,495
Provision related to current period sales | 95,239 | 62,177
Credits/payments made for current period sales | (32,364) | (34,400)
Credits/payments made for prior period sales | (29,067) | (19,325)
Ending balance | 63,069 | 27,947
Rebates, Chargebacks and Discounts |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Beginning balance | 90,997 | 41,634
Provision related to current period sales | 437,030 | 274,439
Provision related to prior period sales | (3,872) | (204)
Credits/payments made for current period sales | (304,903) | (184,801)
Credits/payments made for prior period sales | (85,731) | (41,363)
Ending balance | 133,521 | 89,705
Product Returns |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Beginning balance | 4,579 | 2,948
Provision related to current period sales | 2,534 | 1,635
Credits/payments made for current period sales |  | 5
Credits/payments made for prior period sales | (223) | (653)
Ending balance | 6,890 | 3,935
Other Incentives |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Beginning balance | 3,720 | 1,167
Provision related to current period sales | 50,403 | 30,882
Credits/payments made for current period sales | (46,768) | (30,404)
Credits/payments made for prior period sales | (3,721) | (1,199)
Ending balance | $ 3,634 | $ 446

X
- Definition Credits/payments made for prior period sales. + References No definition available. + Details
Name: | amrn_CreditsPaymentsMadeForPriorPeriodSales
Namespace Prefix: | amrn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Provision related to prior period sales. + References No definition available. + Details
Name: | amrn_ProvisionRelatedToPriorPeriodSales
Namespace Prefix: | amrn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Valuation allowances provisions and reserves balance net. + References No definition available. + Details
Name: | amrn_ValuationAllowancesProvisionsAndReservesBalanceNet
Namespace Prefix: | amrn_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | srt_ValuationAndQualifyingAccountsDisclosureLineItems
Namespace Prefix: | srt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column C)(1)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
Name: | us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of decrease in valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column D)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
Name: | us-gaap_ValuationAllowancesAndReservesDeductions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_ValuationAllowancesAndReservesTypeAxis=us-gaap_AllowanceForCreditLossMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowancesAndReservesTypeAxis=amrn_RebatesChargebacksAndDiscountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowancesAndReservesTypeAxis=amrn_ProductReturnsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowancesAndReservesTypeAxis=amrn_OtherIncentiveProgramsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |