Equity - Shares and Units (Details)	9 Months Ended
	Sep. 30, 2021 USD ($) shares	May 16, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP Unit, redemption term for cash (in years)	1 year
OP Unit, exchange ratio to common stock	1
Conversion rate tor LTIP units to OP units	1
Dividends on common stock received until performance criteria met for LTIP units (as a percent)	10.00%
Dividends on common stock received after performance criteria met for LTIP units (as a percent)	90.00%
Dividends on common stock received in periods after performance criteria met for LTIP units (as a percent)	100.00%
OP units outstanding (in shares)	285,104,512
Stock repurchase authorized amount | $	$ 500,000,000
Empire state realty trust
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units owned by the Company (in shares)	173,292,301
Other partners, certain directors, officers and other members of executive management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units not owned by the Company (in shares)	111,812,211
Empire state realty OP | Empire state realty trust
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units owned by the Company (as a percent)	60.80%
Empire state realty OP | Other partners, certain directors, officers and other members of executive management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
OP units not owned by the Company (as a percent)	39.20%
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the plan (in shares)	11,000,000	11,000,000