Debt Instrument, Number of Properties Collateralizing Loan

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- Definition

Debt Instrument, Periodic Principal Payment, Percent

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No definition available.

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- Definition

Guarantor Obligations, Recourse Triggering Event, Equity Capitalization Amount

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- Definition

Guarantor Obligations, Recourse Triggering Event, Net Assets

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- Definition

Represents the percentage of principal amount used in the computation of issue price for the line of credit facility.

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No definition available.

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- Definition

The value of the financial instrument(s) that the original debt is being converted into 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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- Definition

The number of shares issued in exchange for 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 payments in the period.

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- Definition

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

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- Definition

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

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- Definition

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

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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.

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No definition available.

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- Definition

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

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- 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.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt Obligations, net (Narrative) (Details) shares in Millions	1 Months Ended				12 Months Ended
	Jun. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($) property	Nov. 30, 2016 USD ($) shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 31, 2017 USD ($)	Aug. 31, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2015 USD ($)
Debt Instrument [Line Items]
Loss on early extinguishment of debt, net					$ 10,367,000	$ 14,724,000	$ 1,619,000
Repayment of principal amount					944,800,000	1,921,699,000	1,442,938,000
Conversion of senior unsecured convertible notes into common stock					$ 0	0	9,596,000
2017 Secured Financing
Debt Instrument [Line Items]
Debt instrument, face amount			$ 227,000,000.0
Stated interest rate (percent)			3.795%
Number of properties collateralizing loan \| property			12
Deferred financing costs			$ 7,300,000
2016 Senior Term Loan \| LIBOR
Debt Instrument [Line Items]
Basis point spread on variable interest rate (percent)					1.00%
4.625% senior notes
Debt Instrument [Line Items]
Stated interest rate (percent)					4.625%
5.25% senior notes
Debt Instrument [Line Items]
Stated interest rate (percent)					5.25%
3.125% senior convertible notes
Debt Instrument [Line Items]
Stated interest rate (percent)		3.125%			3.125%
Safety, Income and Growth, Inc. \| 2017 Secured Financing
Debt Instrument [Line Items]
Equity capitalization amount, at least					$ 500,000,000.0
Net worth, at least					$ 250,000,000.0
Secured Debt \| 2017 Secured Financing
Debt Instrument [Line Items]
Debt instrument, face amount			$ 227,000,000.0
Secured Debt \| 2016 Senior Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount	$ 650,000,000.0	$ 400,000,000.0							$ 500,000,000.0	$ 450,000,000.0
Percentage of par credit facilities were issued at										99.00%
Periodic principal payment (as a percent)					0.25%
Secured Debt \| 2016 Senior Term Loan \| LIBOR
Debt Instrument [Line Items]
Basis point spread on variable interest rate (percent)	2.75%	3.00%			2.75%
Secured Debt \| 2016 Senior Term Loan \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis point spread on variable interest rate (percent)		0.75%
Secured Debt \| 2016 Senior Term Loan \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis point spread on variable interest rate (percent)					1.75%
Secured Debt \| 2015 Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity											$ 250,000,000.0
Secured Debt \| 2015 $325 Million Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, face amount					$ 325,000,000
Maximum borrowing capacity		$ 325,000,000.0			$ 325,000,000.0
Secured Debt \| 2015 $325 Million Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage					0.30%
Repayments of credit facility					$ 325,000,000
Current borrowing capacity					$ 325,000,000
Secured Debt \| 2015 $325 Million Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage					0.50%
Secured Debt \| 2015 $325 Million Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis point spread on variable interest rate (percent)					2.50%
Secured Debt \| 2015 $325 Million Revolving Credit Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis point spread on variable interest rate (percent)					1.00%
Secured Debt \| Other expense \| 2016 Senior Term Loan
Debt Instrument [Line Items]
Loss on early extinguishment of debt, net					$ 2,500,000	800,000
Unsecured Notes
Debt Instrument [Line Items]
Loss on early extinguishment of debt, net					$ 1,200,000	$ 13,600,000	$ 400,000
Debt issuance costs incurred		18,600,000
Unsecured Notes \| 4.625% senior notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 400,000,000.0
Stated interest rate (percent)		4.625%
Unsecured Notes \| 5.25% senior notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 400,000,000.0
Stated interest rate (percent)		5.25%
Unsecured Notes \| 3.125% senior convertible notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 250,000,000.0						$ 37,500,000
Stated interest rate (percent)		3.125%			3.125%
Unsecured Notes \| 4.00% senior notes
Debt Instrument [Line Items]
Stated interest rate (percent)		4.00%
Extinguishment of debt		$ 550,000,000
Unsecured Notes \| 7.125% senior notes
Debt Instrument [Line Items]
Stated interest rate (percent)		7.125%
Extinguishment of debt		$ 300,000,000
Unsecured Notes \| 4.875% senior notes
Debt Instrument [Line Items]
Stated interest rate (percent)		4.875%
Extinguishment of debt		$ 300,000,000
Unsecured Notes \| 3.00% senior convertible notes
Debt Instrument [Line Items]
Stated interest rate (percent)				3.00%
Repayment of principal amount				$ 200,000,000
Conversion of senior unsecured convertible notes into common stock				$ 9,600,000
Shares of common stock converted (in shares) \| shares				0.8