Basis of Presentation and Significant Accounting Policies - Summary of Reconciliation Net Income (Loss) Attributable to Estimated Taxable Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Net income (loss) attributable to Paramount Group, Inc.	$ (6,793)	$ (10,214)	$ 103,016	$ 372	$ (6,489)	$ (139)	$ 3,188	$ (6,494)	$ 86,381	$ (9,934)	$ (4,419)
Book to tax differences:
Straight-lining of rents and amortization of above and below-market leases, net									(44,083)	(51,880)	(36,131)
Depreciation and amortization									96,991	95,489	104,399
Stock-based compensation									14,441	9,673	5,794
Gain on sale of real estate									(95,182)
Swap breakage costs									(1,487)	(25,367)	(27,147)
Unrealized gain on interest rate swaps									(860)	(4,651)	(29,586)
Valuation allowance on preferred equity investment									4,327
Earnings of unconsolidated joint ventures, including real estate investments									(8,600)	(3,513)	(12,909)
Other, net									1,885	13,295	7,356
Estimated taxable income									$ 53,813	$ 23,112	$ 7,357