Represents the percentage of extension fee to be paid for exercising the option of extending the maturity term.

No definition available.

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- Definition

Represents the fixed charge coverage ratio as of the balance sheet date.

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No definition available.

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Represents the fixed charge coverage ratio as per the financial covenant, defined as adjusted consolidated earnings before interest, taxes, depreciation and amortization to consolidated fixed charges.

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No definition available.

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Represents the leverage ratio as of the balance sheet date.

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No definition available.

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Represents the leverage ratio as per the financial covenant defined as consolidated total indebtedness to total gross asset value.

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No definition available.

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- Definition

Represents the number of options to extend the mortgage loan term.

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No definition available.

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Represents the secured debt ratio as of the balance sheet date.

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No definition available.

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Represents the secured debt ratio defined as consolidated total secured debt to total gross asset value as per the financial covenant.

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No definition available.

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- Definition

Represents the unhedged variable rate debt ratio as of the balance sheet date.

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No definition available.

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Represents the unhedged variable rate debt ratio as per the financial covenant defined as unhedged variable indebtedness to gross asset value.

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No definition available.

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- Definition

Represents the increase in the maximum borrowing capacity allowed as per the accordion feature 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 ("accordion option").

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No definition available.

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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-Name Regulation S-X (SX)
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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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No definition available.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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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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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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

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Percentage of an entity's outstanding debt that is designated as a hedged item in cash flow, fair value, or net investment hedge.

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No definition available.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Debt (Details)								12 Months Ended
Debt (Details)	Feb. 06, 2016	Feb. 02, 2016 USD ($)	Sep. 30, 2015	Jun. 24, 2015 USD ($)	Apr. 09, 2015	Feb. 03, 2014	Jan. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) item	Feb. 01, 2016 USD ($)	Dec. 31, 2014 USD ($)
Debt
Interest rate as of reporting date (as a percent)					2.93%	3.23%
Debt								$ 391,007,000		$ 317,679,000
Total principal outstanding								392,250,000		318,500,000
Unamortized deferred financing costs								(1,243,000)		$ (821,000)
Term of loan facility					5 years	5 years
Credit Agreement \| Operating partnership
Debt
Commitment under the credit agreement		$ 600,000,000		$ 500,000,000				$ 500,000,000	$ 600,000,000
Number of options available for extensions \| item								1
Extension fee (as a percent)								0.10%
Revolving Credit Facility
Debt
Interest rate as of reporting date (as a percent)								1.98%		2.17%
Debt								$ 142,250,000		$ 218,500,000
Commitment under the credit agreement								350,000,000
Letters of credit outstanding								6,300,000
Amount available for borrowing under the facility								$ 201,400,000
Leverage ratio (as a percent)								16.70%
Secured debt ratio (as a percent)								0.00%
Fixed charge coverage ratio								10.1
Unhedged variable rate debt ratio (as a percent)								8.90%
Revolving Credit Facility \| Operating partnership
Debt
Commitment under the credit agreement		800,000,000		350,000,000				$ 700,000,000
Revolving Credit Facility \| Minimum
Debt
Fixed charge coverage ratio, Covenant								1.70
Revolving Credit Facility \| Maximum
Debt
Leverage ratio, Covenant (as a percent)								60.00%
Secured debt ratio, Covenant (as a percent)								40.00%
Unhedged variable rate debt ratio, Covenant (as a percent)								30.00%
Revolving Credit Facility \| LIBOR \| Operating partnership
Debt
Interest rate margin (as a percent)								1.55%
Leverage ratio (as a percent)								16.70%
Revolving Credit Facility \| LIBOR \| Minimum \| Operating partnership
Debt
Interest rate margin (as a percent)								1.55%
Revolving Credit Facility \| LIBOR \| Maximum \| Operating partnership
Debt
Interest rate margin (as a percent)								2.25%
Revolving Credit Facility \| Base rate \| Operating partnership
Debt
Reference rate								base rate
Revolving Credit Facility \| Base rate \| Minimum
Debt
Interest rate margin (as a percent)								0.55%
Revolving Credit Facility \| Base rate \| Maximum
Debt
Interest rate margin (as a percent)								1.25%
Revolving Credit Facility Prior Facility
Debt
Commitment under the credit agreement				405,000,000
2020 Senior Unsecured Term Loan
Debt
Interest rate as of reporting date (as a percent)								2.43%
Debt								$ 150,000,000
Interest rate margin (as a percent)								2.93%
2020 Senior Unsecured Term Loan \| Operating partnership
Debt
Commitment under the credit agreement				150,000,000
Unsecured term loan				$ 150,000,000
Term of loan facility				5 years
Percentage of debt hedged								50.00%
Amount borrowed under term loan or revolving credit facility								$ 75,000,000
2020 Senior Unsecured Term Loan \| LIBOR \| Operating partnership
Debt
Interest rate margin (as a percent)			1.50%
Leverage ratio (as a percent)			16.70%
2020 Senior Unsecured Term Loan \| LIBOR \| Minimum \| Operating partnership
Debt
Interest rate margin (as a percent)								1.50%
2020 Senior Unsecured Term Loan \| LIBOR \| Maximum \| Operating partnership
Debt
Interest rate margin (as a percent)								2.20%
2020 Senior Unsecured Term Loan \| Base rate \| Minimum \| Operating partnership
Debt
Interest rate margin (as a percent)								0.50%
2020 Senior Unsecured Term Loan \| Base rate \| Maximum \| Operating partnership
Debt
Interest rate margin (as a percent)								1.20%
2021 Senior Unsecured Term Loan
Debt
Commitment under the credit agreement									$ 500,000,000
Unsecured term loan		$ 100,000,000
Term of loan facility		5 years
2021 Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)	1.50%
2021 Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)	2.20%
2021 Senior Unsecured Term Loan \| Base rate \| Minimum
Debt
Interest rate margin (as a percent)	0.50%
2021 Senior Unsecured Term Loan \| Base rate \| Maximum
Debt
Interest rate margin (as a percent)	1.20%
2019 Senior Unsecured Term Loan
Debt
Interest rate as of reporting date (as a percent)								3.23%
Debt								$ 100,000,000		$ 100,000,000
Commitment under the credit agreement							$ 100,000,000
Term of loan facility							5 years
2019 Senior Unsecured Term Loan \| Operating partnership
Debt
Commitment under the credit agreement							$ 200,000,000
Total increase in commitment under accordion feature							$ 100,000,000
2019 Senior Unsecured Term Loan \| LIBOR \| Operating partnership
Debt
Interest rate margin (as a percent)								1.75%
Leverage ratio (as a percent)								16.70%
2019 Senior Unsecured Term Loan \| LIBOR \| Minimum \| Operating partnership
Debt
Interest rate margin (as a percent)								1.75%
2019 Senior Unsecured Term Loan \| LIBOR \| Maximum \| Operating partnership
Debt
Interest rate margin (as a percent)								2.65%
2019 Senior Unsecured Term Loan \| Base rate \| Minimum \| Operating partnership
Debt
Interest rate margin (as a percent)								0.75%
2019 Senior Unsecured Term Loan \| Base rate \| Maximum \| Operating partnership
Debt
Interest rate margin (as a percent)								1.65%