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Increase (decrease) in the Applicable Limit under the agreement. The Applicable Limit is the maximum principal amount available for drawing at any relevant time under the agreement.

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The number of consecutive, periodic payment installments in which the debt is to be repaid.

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No definition available.

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The number of consecutive payment installments that can be deferred prior to the balloon installment.

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No definition available.

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- Definition

This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

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- Definition

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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- Definition

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

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- Definition

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

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

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

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- Definition

Amount of the required periodic payments applied to principal.

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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No definition available.

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- 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.

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No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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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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Schedule I- Condensed Financial Information of Seanergy Maritime Holdings Corp. (Parent Company Only), Notes to Financial Statements - 20F (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Mar. 12, 2015 USD ($) Installment $ / shares	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2016 USD ($)	Dec. 14, 2015 USD ($)	Dec. 01, 2015 USD ($)	Sep. 07, 2015 USD ($) $ / shares
Convertible Promissory Notes [Abstract]
Secured loan facilities		$ 178,447	$ 0		$ 178,064
Parent Company [Member]
Basis of Presentation [Abstract]
Cash dividends from subsidiaries		0	$ 0	$ 0
Guarantee [Abstract]
Maximum potential amount under guarantee		$ 178,447
Parent Company [Member] \| Unsecured Convertible Promissory Note [Member] \| Jelco [Member]
Convertible Promissory Notes [Abstract]
Convertible promissory notes	$ 4,000
Number of periodic payments \| Installment	10
Frequency of periodic payment		Semi-annual
Semi-annual installment payment	$ 200
Balloon payment	$ 2,000
Maturity date		Mar. 19, 2020
Conversion price of convertible notes into common stock (in dollars per share) \| $ / shares	$ 0.90
Parent Company [Member] \| Unsecured Convertible Promissory Note [Member] \| Jelco [Member] \| Maximum [Member]
Convertible Promissory Notes [Abstract]
Number of consecutive payment installments that can be deferred \| Installment	3
Parent Company [Member] \| Unsecured Revolving Convertible Note [Member] \| Jelco [Member]
Convertible Promissory Notes [Abstract]
Convertible promissory notes								$ 6,765
Decrease in Applicable Limit						$ (2,000)		$ (1,000)
Conversion price of convertible notes into common stock (in dollars per share) \| $ / shares								$ 0.90
Maximum principal amount available to be drawn						$ 11,765	$ 9,765
Secured loan facilities		$ 11,765
Parent Company [Member] \| Unsecured Revolving Convertible Note [Member] \| Jelco [Member] \| Maximum [Member]
Convertible Promissory Notes [Abstract]
Tenor of note		5 years