Represents the maximum percentage of concentration risk that is not individually disclosed.

No definition available.

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- Definition

Represents the number of collective bargaining arrangements.

+ References

No definition available.

+ Details

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- Definition

Represents the number of tenants to whom the facility is leased.

+ References

No definition available.

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- Definition

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

+ References

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- Definition

Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

+ References

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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.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Publisher FASB
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-Section S99
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-Subparagraph (SX 210.3-04)
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- Definition

The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 505
-SubTopic 30
-Section 50
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- Details

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Significant Accounting Policies - Concentrations of Credit Risk/Reclassification (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) Tenant agreement	Dec. 31, 2017 USD ($)	Dec. 31, 2016
Concentration of Credit Risk
Common shares	$ 847	$ 939
Additional paid-in-capital	4,508,685	4,968,338
Treasury shares	(124,049)	(124,049)
Retained earnings	$ 1,278,998	$ 1,139,329
Annualized rent \| Customer concentration
Concentration of Credit Risk
Number of tenants (tenants) \| Tenant	1
Maximum percentage of annualized rent for any one tenant not individually disclosed (percent) (more than)	5.00%
Annualized rent \| 1515 Broadway \| Customer concentration
Concentration of Credit Risk
Percentage of concentration	6.00%	7.00%	8.80%
Annualized rent \| 1185 Avenue of the Americas \| Customer concentration
Concentration of Credit Risk
Percentage of concentration	6.70%	7.10%	6.90%
Annualized rent \| 11 Madison Avenue \| Customer concentration
Concentration of Credit Risk
Percentage of concentration	7.40%	7.10%	6.10%
Annualized rent \| 420 Lexington Avenue \| Customer concentration
Concentration of Credit Risk
Percentage of concentration	6.50%	6.00%	5.90%
Annualized rent \| One Madison Ave \| Customer concentration
Concentration of Credit Risk
Percentage of concentration	5.80%	5.60%	5.60%
Collective bargaining arrangements \| Workforce concentration
Concentration of Credit Risk
Percentage of concentration	68.70%
Number of collective bargaining agreements \| agreement	6
Collective bargaining arrangements expiring in December 2019 \| Workforce concentration
Concentration of Credit Risk
Percentage of concentration	56.00%
Tenant 1 \| Annualized rent \| Customer concentration
Concentration of Credit Risk
Percentage of concentration	8.20%