Significant Accounting Policies - Cost Capitalization (Details)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Period in which the company capitalizes interest, real estate taxes and certain operating expenses on the unoccupied portion of recently completed properties, beginning with the date it is substantially complete (percent)	90.00%
Period in which the company capitalizes interest, real estate taxes and certain operating expenses on the unoccupied portion of recently completed properties, beginning with the date it is substantially complete (in years)	1 year