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Judgment amount for acceleration of indebtedness.

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Warrant expiration date.

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Exercise price per share or per unit of warrants or rights outstanding.

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The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Discussion of whether the debt instrument is secured or unsecured, and, if secured, a description of the collateral and guarantees required or provided.

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Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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The price per share of the conversion feature embedded in the debt instrument.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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

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Increase for accrued, but unpaid interest on the debt instrument for the period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of a subjective acceleration clause that is a part of the debt instrument. A subjective acceleration clause is a provision in a debt agreement that states that the creditor may accelerate the scheduled maturities of the obligation under conditions that are not objectively determinable (for example, if the debtor fails to maintain satisfactory operations or if a material adverse change occurs).

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Loans Payable - Note 4 - Epsilon - Additional Information (Detail) $ / shares in Units, Cuota in Millions									3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 10, 2017 USD ($)	Apr. 10, 2017 USD ($) shares	Mar. 21, 2017 USD ($) shares	Dec. 15, 2016 $ / shares shares	Nov. 15, 2016 $ / shares shares	Oct. 16, 2016 $ / shares shares	Oct. 01, 2016 USD ($) d $ / shares shares	Mar. 18, 2016 USD ($) d Cuota $ / shares	Sep. 30, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Cuota $ / shares	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2017 USD ($)	Aug. 21, 2020 $ / shares shares	Jul. 31, 2020 $ / shares	Jan. 25, 2017 USD ($)	Mar. 17, 2016 $ / shares
Debt Instrument [Line Items]
Aggregate amount issuable							$ 3,000,000
Conversion price of Notes \| $ / shares									$ 4.86		$ 4.86					$ 3.71
Common stock purchase warrant \| shares															1,901,989
Warrant right exercise price \| $ / shares															$ 4.75
Epsilon Acquisitions, LLC [Member]
Debt Instrument [Line Items]
Aggregate amount issuable								$ 6,000,000
Accrued interest									$ 25,205	$ 25,205	$ 75,067	$ 74,795
Aggregate fair value of warrants													$ 303,712
Inducement expense													303,712
Notes Payable, Other Payables [Member] \| Third Tranche [Member]
Debt Instrument [Line Items]
Conversion price of Notes \| $ / shares						$ 3.52
Conversion of stock, shares Issued \| shares						1,000,000
Notes Payable, Other Payables [Member] \| Fourth Tranche [Member]
Debt Instrument [Line Items]
Conversion price of Notes \| $ / shares					$ 4.19
Conversion of stock, shares Issued \| shares					1,000,000
Notes Payable, Other Payables [Member] \| Fifth Tranche [Member]
Debt Instrument [Line Items]
Conversion price of Notes \| $ / shares				$ 4.13
Conversion of stock, shares Issued \| shares				1,000,000
Notes Payable, Other Payables [Member] \| MINOSA [Member]
Debt Instrument [Line Items]
Aggregate amount issuable								14,750,000
Debt Instrument, acceleration clause description											The indebtedness may be accelerated upon the occurrence of specified events of default including (a) OME's failure to pay any amount payable on the date due and payable; (b) OME or we fail to perform or observe any term, covenant, or agreement in the Purchase Agreement or the related documents, subject to a five-day cure period; (c) an event of default or material breach by OME, us or any of our affiliates under any of the other loan documents shall have occurred and all grace periods, if any, applicable thereto shall have expired; (d) the Stock Purchase Agreement shall have been terminated; (e) specified dissolution, liquidation, insolvency, bankruptcy, reorganization, or similar cases or actions are commenced by or against OME or any of its subsidiaries, in specified circumstances unless dismissed or stayed within 60 days; (f) the entry of judgment or award against OME or any of its subsidiaries in excess or $100,000; and (g) a change in control (as defined in the Purchase Agreement) occurs.
Judgment amount for acceleration of indebtedness								100,000
Notes Payable, Other Payables [Member] \| Epsilon Acquisitions, LLC [Member]
Debt Instrument [Line Items]
Aggregate amount issuable			$ 6,000,000				$ 3,000,000	3,000,000									$ 3,000,000
Installment amount of Notes								$ 1,500,000
Interest rate, stated percentage							10.00%	10.00%
Notes security description											we granted security interests to Epsilon in (a) the 54 million cuotas (a unit of ownership under Panamanian law) of Oceanica Resources S. de R.L. (“Oceanica”) held by our wholly owned subsidiary, Odyssey Marine Enterprises, Ltd. (“OME”), (b) all notes and other receivables from Oceanica and its subsidiary owed to the Odyssey Pledgors, and (c) all of the outstanding equity in OME.
Conversion price of Notes \| $ / shares							$ 5.00	$ 5.00										$ 5.00
Conversion price of Notes upon default \| $ / shares								$ 2.50
Debt instrument maturity date								Mar. 18, 2017			Mar. 18, 2017
Pledged units of ownership \| Cuota								54			54
Number of trading days \| d							75	75
Lender's out of pocket costs													50,000
Accrued interest		$ 302,274
Conversion of stock, shares Issued \| shares		670,455	670,455
Beneficial conversion feature recorded													96,000
Debt conversion amount	$ 2,000,000		$ 2,000,000											$ 2,000,000
Common stock purchase warrant \| shares							120,000
Warrant right exercise price \| $ / shares							$ 3.52
Warrant Expiration Date											Oct. 01, 2021
Warrant right exercise price description											Warrant shall be the number determined by multiplying 120,000 by a fraction, (a) the numerator of which is the aggregate principal amount of advances that have been extended to the OME by Epsilon pursuant to the Restated Note Purchase Agreement on or after the date of the Warrant and prior to the date of such failure and (b) the denominator of which is $3.0 million.
Equity component in loans payable			3,000,000						3,000,000	$ 3,000,000	$ 3,000,000	$ 3,000,000	3,000,000
Amount of loan outstanding									$ 1,000,000		$ 1,000,000		$ 1,000,000
Notes Payable, Other Payables [Member] \| Epsilon Acquisitions, LLC [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Aggregate amount issuable			$ 6,050,000
Notes Payable, Other Payables [Member] \| Epsilon Acquisitions, LLC [Member] \| Maximum [Member] \| Tranche [Member]
Debt Instrument [Line Items]
Conversion of stock, shares Issued \| shares							1,388,769