220 Central Park South 220 CPS	6 Months Ended
	Jun. 30, 2021
Real Estate [Abstract]
220 Central Park South 220 CPS	220 Central Park South ("220 CPS")During the three and six months ended June 30, 2021, we closed on the sale of three condominium units at 220 CPS for net proceeds of $72,216,000 resulting in a net gain of $25,272,000 which is included in "net gains on disposition of wholly owned and partially owned assets" on our consolidated statements of income. In connection with these sales, $3,064,000 of income tax expense was recognized on our consolidated statements of income. From inception to June 30, 2021, we have closed on the sale of 103 units for net proceeds of $2,941,708,000 resulting in financial statement net gains of $1,092,209,000.