Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Operating Activities
Net income	$ 113,279	$ 193,741
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	127,417	169,381
Equity in net loss from unconsolidated joint ventures	15,834	15,013
Distributions of cumulative earnings from unconsolidated joint ventures	174	206
Equity in net loss on sale of interest in unconsolidated joint venture interest/real estate	4,158	0
Purchase price and other fair value adjustments	(717)	0
Depreciable real estate reserves and impairment	5,696	0
Gain on sale of real estate, net	(97,572)	(137,520)
Loan loss reserves and other investment reserves, net of recoveries	0	18,061
Deferred rents receivable	(7,144)	2,577
Non-cash lease expense	7,538	6,547
Other non-cash adjustments	18,137	7,648
Changes in operating assets and liabilities:
Tenant and other receivables	(2,493)	(57,325)
Related party receivables	(2,055)	4,395
Deferred lease costs	(3,602)	(11,143)
Other assets	15,550	(17,363)
Accounts payable, accrued expenses, other liabilities and security deposits	(60,592)	39,318
Deferred revenue	888	(3,503)
Lease liability - operating leases	(31,232)	(5,728)
Net cash provided by operating activities	103,264	224,305
Investing Activities
Acquisitions of real estate property	(28,688)	(86,846)
Additions to land, buildings and improvements	(118,076)	(183,297)
Investments in unconsolidated joint ventures	(38,198)	(18,318)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	417,457	76,091
Net proceeds from disposition of real estate/joint venture interest	398,173	249,820
Cash assumed from consolidation of real estate investment	9,475	0
Proceeds from sale or redemption of marketable securities	4,528	0
Purchases of marketable securities	(10,000)	0
Other investments	(4,108)	(7,324)
Origination of debt and preferred equity investments	(74,148)	(265,574)
Repayments or redemption of debt and preferred equity investments	85,106	639,267
Net cash provided by investing activities	641,521	403,819
Financing Activities
Proceeds from mortgages and other loans payable	19,772	642,196
Repayments of mortgages and other loans payable	(364,994)	(266,795)
Proceeds from revolving credit facility and unsecured notes	570,000	1,275,000
Repayments of revolving credit facility and unsecured notes	(680,000)	(815,000)
Proceeds from stock options exercised and DRSPP issuance	467	364
Repurchase of common stock	(178,666)	(352,048)
Redemption of preferred stock	(3,631)	(59,800)
Redemption of OP units	(13,930)	(18,066)
Distributions to noncontrolling interests in other partnerships	(173)	(596)
Contributions from noncontrolling interests in other partnerships	305	8,186
Acquisition of subsidiary interest from noncontrolling interest	0	(1,536)
Distributions to noncontrolling interests in the Operating Partnership	(8,110)	(5,110)
Dividends paid on common and preferred stock	(138,373)	(153,474)
Tax withholdings related to restricted share awards	(2,842)	(4,752)
Deferred loan costs	(470)	(16,510)
Principal payments of on financing lease liabilities	(434)	(330)
Net cash (used in) provided by financing activities	(801,079)	231,729
Net (decrease) increase in cash, cash equivalents, and restricted cash	(56,294)	859,853
Cash, cash equivalents, and restricted cash at beginning of year	372,795	241,430
Cash, cash equivalents, and restricted cash at end of period	316,501	1,101,283
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Conversion of units in the Operating Partnership	0	8,744
Redemption of units in the Operating Partnership for a joint venture sale	27,586	0
Exchange of preferred equity investment for real estate or equity in joint venture	0	119,467
Issuance of special dividend paid primarily in stock	123,529	0
Tenant improvements and capital expenditures payable	8,911	6,653
Fair value adjustment to noncontrolling interest in the Operating Partnership	32,475	31,144
Consolidation of real estate investment	119,444	0
Reversal of assets held for sale	0	391,664
Extinguishment of debt in connection with property dispositions	53,548	0
Seller financed purchases	0	100,000
Debt and preferred equity investments	5,184	4,638
Transfer of assets related to assets held for sale	0	49,687
Transfer of liabilities related to assets held for sale	0	38,272
Removal of fully depreciated commercial real estate properties	4,288	534
Share repurchase payable	20,221	8,820
Recognition of right of use assets and related lease liabilities	119,711	114,974
Cash and cash equivalents	218,337	1,015,348
Restricted cash	98,164	85,935
Total cash, cash equivalents, and restricted cash	316,501	1,101,283
SL Green Operating Partnership
Operating Activities
Net income	113,279	193,741
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	127,417	169,381
Equity in net loss from unconsolidated joint ventures	15,834	15,013
Distributions of cumulative earnings from unconsolidated joint ventures	174	206
Equity in net loss on sale of interest in unconsolidated joint venture interest/real estate	4,158	0
Purchase price and other fair value adjustments	(717)	0
Depreciable real estate reserves and impairment	5,696	0
Gain on sale of real estate, net	(97,572)	(137,520)
Loan loss reserves and other investment reserves, net of recoveries	0	18,061
Deferred rents receivable	(7,144)	2,577
Non-cash lease expense	7,538	6,547
Other non-cash adjustments	18,137	7,648
Changes in operating assets and liabilities:
Tenant and other receivables	(2,493)	(57,325)
Related party receivables	(2,055)	4,395
Deferred lease costs	(3,602)	(11,143)
Other assets	15,550	(17,363)
Accounts payable, accrued expenses, other liabilities and security deposits	(60,592)	39,318
Deferred revenue	888	(3,503)
Lease liability - operating leases	(31,232)	(5,728)
Net cash provided by operating activities	103,264	224,305
Investing Activities
Acquisitions of real estate property	(28,688)	(86,846)
Additions to land, buildings and improvements	(118,076)	(183,297)
Investments in unconsolidated joint ventures	(38,198)	(18,318)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	417,457	76,091
Net proceeds from disposition of real estate/joint venture interest	398,173	249,820
Cash assumed from consolidation of real estate investment	9,475	0
Proceeds from sale or redemption of marketable securities	4,528	0
Purchases of marketable securities	(10,000)	0
Other investments	(4,108)	(7,324)
Origination of debt and preferred equity investments	(74,148)	(265,574)
Repayments or redemption of debt and preferred equity investments	85,106	639,267
Net cash provided by investing activities	641,521	403,819
Financing Activities
Proceeds from mortgages and other loans payable	19,772	642,196
Repayments of mortgages and other loans payable	(364,994)	(266,795)
Proceeds from revolving credit facility and unsecured notes	570,000	1,275,000
Repayments of revolving credit facility and unsecured notes	(680,000)	(815,000)
Proceeds from stock options exercised and DRSPP issuance	467	364
Repurchase of common stock	(178,666)	(352,048)
Redemption of preferred stock	(3,631)	(59,800)
Redemption of OP units	(13,930)	(18,066)
Distributions to noncontrolling interests in other partnerships	(173)	(596)
Contributions from noncontrolling interests in other partnerships	305	8,186
Acquisition of subsidiary interest from noncontrolling interest	0	(1,536)
Dividends paid on common and preferred stock	(146,483)	(158,584)
Tax withholdings related to restricted share awards	(2,842)	(4,752)
Deferred loan costs	(470)	(16,510)
Principal payments of on financing lease liabilities	(434)	(330)
Net cash (used in) provided by financing activities	(801,079)	231,729
Net (decrease) increase in cash, cash equivalents, and restricted cash	(56,294)	859,853
Cash, cash equivalents, and restricted cash at beginning of year	372,795	241,430
Cash, cash equivalents, and restricted cash at end of period	316,501	1,101,283
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Conversion of units in the Operating Partnership	0	8,744
Redemption of units in the Operating Partnership for a joint venture sale	27,586	0
Exchange of preferred equity investment for real estate or equity in joint venture	0	119,467
Issuance of special dividend paid primarily in stock	123,529	0
Tenant improvements and capital expenditures payable	8,911	6,653
Fair value adjustment to noncontrolling interest in the Operating Partnership	32,475	31,144
Consolidation of real estate investment	119,444	0
Reversal of assets held for sale	0	391,664
Extinguishment of debt in connection with property dispositions	53,548	0
Seller financed purchases	0	100,000
Debt and preferred equity investments	5,184	4,638
Transfer of assets related to assets held for sale	0	49,687
Transfer of liabilities related to assets held for sale	0	38,272
Removal of fully depreciated commercial real estate properties	4,288	534
Share repurchase payable	20,221	8,820
Recognition of right of use assets and related lease liabilities	119,711	114,974
Cash and cash equivalents	218,337	1,015,348
Restricted cash	98,164	85,935
Total cash, cash equivalents, and restricted cash	$ 316,501	$ 1,101,283