Debt instrument maximum borrowing capacity.

No definition available.

Name:	gass_DebtInstrumentMaximumBorrowingCapacity
Namespace Prefix:	gass_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Ebitda To Interest Expense Ratio

+ References

No definition available.

+ Details

Name:	gass_EbitdaToInterestExpenseRatio
Namespace Prefix:	gass_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage Of Dividends Paid To Free Cash Flow

+ References

No definition available.

+ Details

Name:	gass_PercentageOfDividendsPaidToFreeCashFlow
Namespace Prefix:	gass_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage Of Total Debt To Total Market Value Adjusted Assets

+ References

No definition available.

+ Details

Name:	gass_PercentageOfTotalDebtToTotalMarketValueAdjustedAssets
Namespace Prefix:	gass_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Term loan financial covenants cash requirement.

+ References

No definition available.

+ Details

Name:	gass_TermLoanFinancialCovenantsCashRequirement
Namespace Prefix:	gass_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Value To Term Loan Ratio

+ References

No definition available.

+ Details

Name:	gass_ValueToTermLoanRatio
Namespace Prefix:	gass_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(8))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

Name:	us-gaap_AmortizationOfFinancingCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of interest capitalized during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

+ Details

Name:	us-gaap_InterestCostsCapitalized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6676-107765

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3044-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

+ Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=gass_TermLoanEnteredIntoOnOctober092008Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=gass_TermLoanEnteredIntoOnSeptember232013Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoOnMay182016Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanRefinancedOnALongTermBasisMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoOnJune122014AndSeptember152016Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoMarch12017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredDecember72017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoOnApril142014Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoOnJuly52019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoOnMarch242014Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoanEnteredIntoOnApril162014Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan25Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan6Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan15Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan4Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan13Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan21Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan24Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gass_TermLoan8Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Long-term Debt - Additional Information (Detail)																							12 Months Ended
Long-term Debt - Additional Information (Detail)	Sep. 30, 2019 USD ($)	Aug. 08, 2019 USD ($)	Aug. 07, 2019	Aug. 06, 2019	Jun. 20, 2019 USD ($)	Apr. 16, 2019 USD ($)	Apr. 12, 2019 USD ($)	Mar. 29, 2019 USD ($)	Mar. 27, 2019 USD ($)	Mar. 20, 2019 USD ($)	Feb. 19, 2019 USD ($)	Jan. 30, 2019	Jan. 16, 2019 USD ($)	Jan. 12, 2019 USD ($)	Aug. 17, 2018 USD ($)	Apr. 27, 2018 USD ($)	Apr. 17, 2018 USD ($)	Mar. 27, 2018 USD ($)	Feb. 08, 2018 USD ($)	Jan. 10, 2018 USD ($)	Dec. 11, 2017 USD ($)	May 16, 2017 USD ($)	Dec. 31, 2019 USD ($) DerivativeInstrument	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jul. 05, 2019 USD ($)	Feb. 01, 2019	Dec. 14, 2018 USD ($)	Dec. 07, 2017 USD ($)	Mar. 01, 2017 USD ($)	May 18, 2016 USD ($)
Debt Instrument [Line Items]
Restricted cash																							$ 1,589,768	$ 3,002,490	$ 3,231,323
Debt Instrument, maximum borrowing capacity																							25,458,432
Proceeds from issuance of debt																							33,480,000
Long-term debt, total																							368,229,303	445,971,281
Repayments of debt	$ 3,419,645							$ 1,036,265			$ 625,000												97,371,978	56,717,059	56,254,073
Term loan financial covenants, cash requirement																							12,065,222
Debt issuance costs, gross																							8,851,636	8,374,435
Amortization of debt issuance costs																							$ 885,191	$ 858,582	$ 690,842
Debt,weighted average interest rate																							4.91%	5.34%	3.97%
Interest expense, debt, total																							$ 19,999,902	$ 22,150,386	$ 15,640,377
Interest costs capitalized																							$ 97,620	0	$ 813,423
Equity Method Investment Ownership Percentage																							50.10%
Term Loan Entered into on October 9, 2008 [Member]
Debt Instrument [Line Items]
Repayments of debt															$ 5,920,000
Term Loan Entered into on September 23, 2013 [Member]
Debt Instrument [Line Items]
Repayments of debt																$ 4,122,370
Maximum [Member]
Debt Instrument [Line Items]
Value to term loan ratio																							135.00%
Percentage of total debt to total market value adjusted assets																							80.00%
Percentage of dividends paid to free cash flow																							50.00%
Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate																							3.00%
Minimum [Member]
Debt Instrument [Line Items]
Value to term loan ratio																							125.00%
EBITDA to interest expense ratio \| DerivativeInstrument																							2.5
Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate																							2.15%
Term Loan Entered Into On May 18, 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, maximum borrowing capacity																															$ 74,480,000
Proceeds from issuance of debt																				$ 33,150,000		$ 32,500,000
Term Loan Refinanced On A Long Term Basis [Member]
Debt Instrument [Line Items]
Long-term debt, total																		$ 27,675,000
Repayments of debt																		$ 275,000
Term Loan Entered into on June 12, 2014 and September 15, 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, maximum borrowing capacity																												$ 23,574,184
Term Loan Entered Into March 1, 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, maximum borrowing capacity																														$ 76,020,000
Proceeds from issuance of debt																	$ 35,262,500			$ 35,525,000
Term Loan Entered December 7, 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, maximum borrowing capacity																													$ 22,500,000
Proceeds from issuance of debt																			$ 11,775,000		$ 10,500,000
Term Loan Entered into on April 14, 2014 [Member]
Debt Instrument [Line Items]
Debt Instrument, maximum borrowing capacity																							$ 11,000,000
Repayments of debt						$ 700,000			$ 15,780,000				$ 700,000
Term Loan Entered into on July 5, 2019 [Member]
Debt Instrument [Line Items]
Restricted cash																										$ 22,230,000
Repayments of debt					$ 1,500,000		$ 1,500,000			$ 1,500,000				$ 1,500,000
Term Loan Entered into on March 24, 2014 [Member]
Debt Instrument [Line Items]
Repayments of debt		$ 3,000,000
Term Loan Entered Into On April 16, 2014 [Member]
Debt Instrument [Line Items]
Repayments of debt									$ 15,780,000
Term Loan 25 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt																							0
Long-term debt, total																							47,595,000	51,555,000
Repayments of debt																							3,960,000
Term Loan 25 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.50%								2.50%
Term Loan 6 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt																							0
Long-term debt, total																							0	23,375,000
Repayments of debt																							23,375,000
Term Loan 6 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.70%
Term Loan 15 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt																							0
Long-term debt, total																							15,843,750	17,468,750
Repayments of debt																							1,625,000
Term Loan 15 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate												3.00%
Term Loan 4 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt																							0
Long-term debt, total																							0	13,850,000
Repayments of debt																							0
Equity Method Investment Ownership Percentage																											49.90%
Term Loan 13 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.90%
Term Loan 21 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt																							0
Long-term debt, total																							21,900,000	25,200,000
Repayments of debt																							3,300,000
Term Loan 21 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.50%
Term Loan 24 [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt																							0
Long-term debt, total																							29,025,000	$ 35,630,000
Repayments of debt																							$ 6,605,000
Term Loan 24 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			2.30%
Term Loan 8 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			2.80%