Debt Instrument, Basis Spread on Variable Rate, Increase (Decrease)

No definition available.

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- Definition

Debt Instrument, Extension Period

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Debt instrument weighted average interest rate.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instruments, Number of Debt Instruments Issued

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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

- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
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- 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

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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

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.

+ References

+ Details

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

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Definition

The aggregate amount of other income amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

+ Details

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

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=land_FarmCreditCentralFloridaNotesPayableMember
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Name:	us-gaap_DebtInstrumentAxis=land_FarmCreditWestNotePayableMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=land_MetlifeFacilityMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=land_TwoThousandFifteenMetLifeTermNoteMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=land_MetLifeLineOfCreditMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=land_TwoThousandSixteenMetLifeTermNoteMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=land_TwoThousandSixteenMetLifeLineofCreditMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=land_FarmerMacBondsPayableMember
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- Details

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- Details

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- Details

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Borrowings - Additional Information (Detail)	1 Months Ended	3 Months Ended
Borrowings - Additional Information (Detail)	May 09, 2017 USD ($)	Mar. 31, 2017 USD ($) debt_instrument	Mar. 31, 2016 USD ($)	Jan. 12, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 05, 2016 USD ($)	Oct. 04, 2016 USD ($)	Jun. 16, 2016 USD ($)	Dec. 05, 2014 USD ($)	May 09, 2014 USD ($)
Debt Instrument [Line Items]
Weighted average interest rate (as percent)		3.25%	3.29%
Other income		$ 184,000	$ 95,000
Borrowings under line of credit		$ 20,050,000			$ 16,550,000
Farm Credit Notes Payable
Debt Instrument [Line Items]
Reduced stated interest rate (as percent)		17.20%
Reduction in basis points (as percent)		0.61%
Farm Credit Central Florida Notes Payable
Debt Instrument [Line Items]
Reduced stated interest rate (as percent)		15.80%
Number of debt instruments \| debt_instrument		8
Other income			94,000
Farm Credit Central Florida Notes Payable \| Subsequent Event
Debt Instrument [Line Items]
Reduction in basis points (as percent)	0.55%
Other income	$ 124,000
Farm Credit West Note Payable
Debt Instrument [Line Items]
Reduced stated interest rate (as percent)		21.30%
Reduction in basis points (as percent)		0.76%
Number of debt instruments \| debt_instrument		2
Other income		$ 59,000	$ 0
MetLife Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 200,000,000	$ 125,000,000
2015 Metlife Term Note (MetLife)
Debt Instrument [Line Items]
Face amount of debt										$ 100,000,000
2015 Metlife Line of Credit (MetLife)
Debt Instrument [Line Items]
Face amount of debt										$ 25,000,000
2016 Metlife Term Note (MetLife)
Debt Instrument [Line Items]
Line of credit, carrying value						50,000,000
2016 Metlife Line of Credit (MetLife)
Debt Instrument [Line Items]
Line of credit, carrying value						$ 25,000,000
Farmer Mac Bonds Payable
Debt Instrument [Line Items]
Face amount of debt		$ 125,000,000						$ 125,000,000	$ 75,000,000
Number of debt instruments \| debt_instrument		13
Extension period of debt		2 years
Farmer Mac Bonds Payable, 2017 Issuances
Debt Instrument [Line Items]
Face amount of debt				$ 32,400,000
Number of debt instruments \| debt_instrument		4
Mortgage notes and bonds payable \| Notes and bonds payables
Debt Instrument [Line Items]
Aggregate fair value of mortgage notes payable outstanding		$ 216,700,000
Mortgage notes payable, carrying value		222,400,000
Short-term variable-rate mortgage notes and bonds payable \| Notes and bonds payables
Debt Instrument [Line Items]
Borrowings under line of credit		$ 20,100,000