Additional distribution amount of general unsecured claims Bankruptcy Settlement Agreement.

No definition available.

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The date the interim distribution was received related to the March 3, 2015 settlement agreement.

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No definition available.

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The amount of cash dividends paid per share to common shareholders.

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No definition available.

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- Definition

Represents the impaired real estate assets as of the end of the reporting period that are valued by the entity at fair value as of the balance sheet date.

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No definition available.

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The interim settlement amount of general unsecured claims distributed in accordance with the approved Bankruptcy Settlement Agreement.

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No definition available.

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The number of properties classified as held for sale and reported as discontinued operations.

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No definition available.

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The number of properties that were sold during the year that previously did not meet the criteria to be classified as held for sale whose gain was reported in continuing operations.

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No definition available.

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Amount of ordinary cash dividend paid during the period for each share of common stock outstanding.

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No definition available.

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Amount of decrease to current year's net earnings resulting from the correction in the current year of a misstatement made in the prior year's financial statements.

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No definition available.

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Cash outflow in the form of a special dividend to common shareholders, preferred shareholders and noncontrolling interests, generally out of earnings.

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No definition available.

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Represents the percentage of annual assumed average rent increases used as an unobservable input to measure the fair value.

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No definition available.

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Amount of special cash dividend paid during the period for each share of common stock outstanding.

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No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Ratio of the net operating income produced by an asset and its capital cost (original prices paid to buy the asset), used as an input to measure fair value.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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- Definition

The gain (loss) is the pre-tax difference between the net condemnation award and the entity's adjusted basis of the condemned property.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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-Name Accounting Standards Codification

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Cash outflow in the form of ordinary dividends to common shareholders, preferred shareholders and noncontrolling interests, generally out of earnings.

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Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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General - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		0 Months Ended
General - Additional Information (Detail) (USD $)	Jun. 30, 2014 Property	Mar. 31, 2015 Property	Mar. 31, 2014	Apr. 22, 2015	Dec. 31, 2014
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of real estate properties held for sale	16
Number of properties sold		2
Loss from sale of properties		$ 194,000us-gaap_GainLossOnSaleOfProperties
Loss on partial condemnation		24,000us-gaap_GainLossOnCondemnation
Impairment charges		7,913,000us-gaap_AssetImpairmentCharges	1,663,000us-gaap_AssetImpairmentCharges
Cash dividends		12,150,000us-gaap_PaymentsOfDividends	8,423,000us-gaap_PaymentsOfDividends
Cash dividends per share		$ 0.36gty_CashDividendsPaidPerShare	$ 0.25gty_CashDividendsPaidPerShare
Payment of regular quarterly cash dividend		7,425,000us-gaap_PaymentsOfOrdinaryDividends	6,738,000us-gaap_PaymentsOfOrdinaryDividends
Payment of special cash dividend		4,725,000gty_PaymentOfSpecialDividend	1,685,000gty_PaymentOfSpecialDividend
Regular quarterly cash dividends paid per share		$ 0.22	$ 0.20
Special cash dividends paid per share		$ 0.14gty_SpecialCashDividendPerShareCashPaid	$ 0.05gty_SpecialCashDividendPerShareCashPaid
Adjustment which decreased net earnings			420,000gty_OutOfPeriodAdjustments
Estimated Sale Price Method [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Impairment charges		7,913,000
Estimated fair value		5,127,000
Discounted Cash Flow Method [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Impairment charges		7,913,000
Estimated fair value		3,000
Accumulation of Asset Retirement Cost Method [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Impairment charges		7,913,000
Estimated fair value		2,783,000
Stock Options [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Anti-dilutive securities Excluded from calculation of EPS		5,000	5,000
Finance Leases Financing Receivable [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Impairment charges		0	0
Marketing Estate Liquidating Trustee [Member] \| Settlement Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Settlement agreement hearing date		Apr. 22, 2015
Subsequent Event [Member] \| Marketing Estate Liquidating Trustee [Member] \| Settlement Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Interim distribution amount				6,800,000
Additional distribution amount				550,000
Level 3 [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Assumed holding periods for unobservable inputs		15 years
Assumed annual average rent increases for unobservable inputs		2.00%
Rate of income capitalization for unobservable inputs		8.00%
Cash flows discounted rate for unobservable inputs		7.00%
Level 3 [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Impaired real estate assets measured at fair value		$ 7,776,000			$ 9,266,000