$SLG
SL Green Realty Corp Stock $slg

$slg Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000104097120000006 Filed on February 28, 2020

Income Statement

Concept	2019 Q4	2019	2018 Q4
Revenue	$308.1M	$1.239B	$317.0M
YoY Change	-2.82%	0.95%	-12.26%
Cost Of Revenue	$114.9M	$458.6M	$109.3M
YoY Change	5.12%	2.21%	-21.08%
Gross Profit	$193.2M	$780.4M	$207.7M
YoY Change	-6.98%	0.22%	-6.78%
Gross Profit Margin	62.71%	62.99%	65.51%
Selling, General & Admin	$25.90M	$100.9M	$26.50M
YoY Change	-2.26%	8.96%	2.32%
% of Gross Profit	13.41%	12.93%	12.76%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$67.20M	$284.0M	$74.10M
YoY Change	-9.31%	-2.03%	-16.46%
% of Gross Profit	34.78%	36.39%	35.68%
Operating Expenses	$90.00M	$100.9M	$103.7M
YoY Change	-13.21%	8.96%	-6.07%
Operating Profit	$103.2M	$679.5M	$104.0M
YoY Change	-0.77%	-0.96%	-7.47%
Interest Expense	-$59.70M	$246.8M	$110.4M
YoY Change	-154.08%	4.28%	-292.33%
% of Operating Profit	-57.85%	36.33%	106.15%
Other Income/Expense, Net	$0.00	-$7.000M	-$220.9M
YoY Change	-100.0%	-96.92%	137.02%
Pretax Income	$24.30M	$291.5M	-$58.30M
YoY Change	-141.68%	7.6%	-223.43%
Income Tax		$1.500M
% Of Pretax Income		0.51%
Net Earnings	$21.17M	$270.4M	-$57.48M
YoY Change	-136.83%	9.37%	-281.22%
Net Earnings / Revenue	6.87%	21.83%	-18.13%
Basic Earnings Per Share	$0.21	$3.29	-$0.73
Diluted Earnings Per Share	$0.21	$3.28	-$0.73
COMMON SHARES
Basic Shares Outstanding	80.11M shares	77.06M shares	85.27M shares
Diluted Shares Outstanding		81.87M shares

Balance Sheet

Concept	2019 Q4	2019	2018 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$196.0M	$166.0M	$158.1M
YoY Change	23.93%	28.68%	1.05%
Cash & Equivalents	$166.1M	$166.0M	$129.5M
Short-Term Investments	$29.89M		$28.64M
Other Short-Term Assets
YoY Change
Inventory	$392.0M	$392.0M
Prepaid Expenses
Receivables	$348.0M	$348.0M	$406.0M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$906.0M	$906.0M	$535.0M
YoY Change	69.35%	69.35%	-41.34%
LONG-TERM ASSETS
Property, Plant & Equipment	$6.724B	$6.724B	$6.415B
YoY Change	4.82%	4.82%	-18.86%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$2.913B	$4.523B	$3.019B
YoY Change	-3.52%	-12.12%	27.76%
Other Assets	$281.0M	$281.0M	$359.0M
YoY Change	-21.73%	-21.73%	3.16%
Total Long-Term Assets	$11.86B	$11.86B	$12.22B
YoY Change	-2.91%	-2.91%	-6.54%
TOTAL ASSETS
Total Short-Term Assets	$906.0M	$906.0M	$535.0M
Total Long-Term Assets	$11.86B	$11.86B	$12.22B
Total Assets	$12.77B	$12.77B	$12.75B
YoY Change	0.12%	0.12%	-8.81%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$167.0M	$167.0M	$147.0M
YoY Change	13.61%	13.61%	7.3%
Accrued Expenses	$404.0M	$404.0M	$27.00M
YoY Change	1396.3%	1396.3%	-28.95%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$713.0M	$713.0M	$319.0M
YoY Change	123.51%	123.51%	-3.63%
LONG-TERM LIABILITIES
Long-Term Debt	$5.553B	$5.553B	$5.585B
YoY Change	-0.57%	-0.57%	-5.31%
Other Long-Term Liabilities	$291.0M	$291.0M	$211.0M
YoY Change	37.91%	37.91%	-47.25%
Total Long-Term Liabilities	$5.844B	$5.844B	$5.796B
YoY Change	0.83%	0.83%	-7.97%
TOTAL LIABILITIES
Total Short-Term Liabilities	$713.0M	$713.0M	$319.0M
Total Long-Term Liabilities	$5.844B	$5.844B	$5.796B
Total Liabilities	$6.556B	$7.042B	$6.115B
YoY Change	7.21%	7.53%	-7.76%
SHAREHOLDERS EQUITY
Retained Earnings	$1.085B		$1.279B
YoY Change	-15.19%		12.26%
Common Stock	$803.0K		$847.0K
YoY Change	-5.19%		-9.8%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$124.0M		$124.0M
YoY Change	0.0%		0.0%
Treasury Stock Shares	1.026M shares		1.055M shares
Shareholders Equity	$5.441B	$5.725B	$5.902B
YoY Change
Total Liabilities & Shareholders Equity	$12.77B	$12.77B	$12.75B
YoY Change	0.12%	0.12%	-8.81%

Cashflow Statement

Concept	2019 Q4	2019	2018 Q4
OPERATING ACTIVITIES
Net Income	$21.17M	$270.4M	-$57.48M
YoY Change	-136.83%	9.37%	-281.22%
Depreciation, Depletion And Amortization	$67.20M	$284.0M	$74.10M
YoY Change	-9.31%	-2.03%	-16.46%
Cash From Operating Activities	$77.10M	$376.5M	$124.0M
YoY Change	-37.82%	-14.74%	-5.13%
INVESTING ACTIVITIES
Capital Expenditures	-$103.3M	$253.0M	-$110.9M
YoY Change	-6.85%	-0.58%	26.45%
Acquisitions
YoY Change
Other Investing Activities	$458.7M	$630.1M	$292.3M
YoY Change	56.93%	-36.78%	57.83%
Cash From Investing Activities	$355.4M	$114.5M	$181.5M
YoY Change	95.81%	-83.2%	85.96%
FINANCING ACTIVITIES
Cash Dividend Paid		$306.4M
YoY Change		-2.18%
Common Stock Issuance & Retirement, Net		$384.4M
YoY Change		-60.76%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-407.6M	-$528.7M	-284.9M
YoY Change	43.07%	-51.68%	-13.03%
NET CHANGE
Cash From Operating Activities	77.10M	$376.5M	124.0M
Cash From Investing Activities	355.4M	$114.5M	181.5M
Cash From Financing Activities	-407.6M	-$528.7M	-284.9M
Net Change In Cash	24.90M	-$37.68M	20.60M
YoY Change	20.87%	-229.55%	-120.75%
FREE CASH FLOW
Cash From Operating Activities	$77.10M	$376.5M	$124.0M
Capital Expenditures	-$103.3M	$253.0M	-$110.9M
Free Cash Flow	$180.4M	$123.5M	$234.9M
YoY Change	-23.2%	-33.99%	7.55%

Facts In Submission

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CY2019	dei	Entity File Number EntityFileNumber	1-13199
CY2019	dei	Entity Registrant Name EntityRegistrantName	SL GREEN REALTY CORP
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MD
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CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	12408000	USD
CY2017	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	16498000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	272358000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	279507000	USD
CY2017	us-gaap	Depreciation And Amortization DepreciationAndAmortization	403320000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	6839000	USD
CY2017	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
CY2019	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	729000	USD
CY2018	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	1099000	USD
CY2017	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	-1834000	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	100875000	USD
CY2018	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	92631000	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	100498000	USD
CY2019	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	1034764000	USD
CY2017	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	1346445000	USD
CY2018	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	1049816000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-34518000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	7311000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	21892000	USD
CY2019	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	76181000	USD
CY2018	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	303967000	USD
CY2017	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	16166000	USD
CY2019	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	69389000	USD
CY2018	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	57385000	USD
CY2017	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	-16749000	USD
CY2018	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	-30757000	USD
CY2017	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	73241000	USD
CY2019	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-7047000	USD
CY2018	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-227543000	USD
CY2017	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-178520000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	0	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	0	USD
CY2017	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	3262000	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-17083000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Profit Loss ProfitLoss	291487000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	270856000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	101069000	USD
CY2019	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	13301000	USD
CY2018	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	12216000	USD
CY2017	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	3995000	USD
CY2019	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-3159000	USD
CY2018	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-6000	USD
CY2017	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-15701000	USD
CY2019	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	10911000	USD
CY2018	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	11384000	USD
CY2017	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	11401000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	270434000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	247262000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	101374000	USD
CY2019	us-gaap	Dividends Preferred Stock DividendsPreferredStock	14950000	USD
CY2018	us-gaap	Dividends Preferred Stock DividendsPreferredStock	14950000	USD
CY2017	us-gaap	Dividends Preferred Stock DividendsPreferredStock	14950000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	255484000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	232312000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	86424000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	81733000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	86753000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	98571000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	86562000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	91530000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	103403000	shares
CY2019	us-gaap	Profit Loss ProfitLoss	291487000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	270856000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	101069000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-47118000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-3622000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	1040000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	1249000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	60000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-4667000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-45869000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3562000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3627000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	245618000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	267294000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	97442000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	21053000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	23594000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-305000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-2276000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-66000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-94000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	226841000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	243766000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	97841000	USD
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7750911000	USD
CY2017	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	85673000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-3533000	USD
CY2017	us-gaap	Dividends Preferred Stock DividendsPreferredStock	14950000	USD
CY2017	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	223000	USD
CY2017	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	21574000	USD
CY2017	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	5712000	USD
CY2017	slg	Adjustmentsto Additional Paidin Capital Equity Componentof Repurchased Senior Notes AdjustmentstoAdditionalPaidinCapitalEquityComponentofRepurchasedSeniorNotes	109776000	USD
CY2017	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	29787000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	848048000	USD
CY2017	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	23314000	USD
CY2017	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	36275000	USD
CY2017	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	30203000	USD
CY2017	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	52446000	USD
CY2017	us-gaap	Dividends Common Stock DividendsCommonStock	305059000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6589454000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest Adjusted Balance1 StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	7159978000	USD
CY2018	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	247256000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-3496000	USD
CY2018	us-gaap	Dividends Preferred Stock DividendsPreferredStock	14950000	USD
CY2018	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	136000	USD
CY2018	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	16303000	USD
CY2018	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	34236000	USD
CY2018	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	17484000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	937795000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	28912000	USD
CY2018	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	5459000	USD
CY2018	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	315116000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	8364000	USD
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	282188000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5947855000	USD
CY2019	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	267275000	USD
CY2019	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	25845000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-43593000	USD
CY2019	us-gaap	Dividends Preferred Stock DividendsPreferredStock	14950000	USD
CY2019	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	334000	USD
CY2019	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	471000	USD
CY2019	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	-34320000	USD
CY2019	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	25763000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	384399000	USD
CY2019	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	58462000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	478000	USD
CY2019	us-gaap	Dividends Common Stock DividendsCommonStock	279377000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5517198000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	291487000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	270856000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	101069000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	284011000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	289899000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	418798000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-34518000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	7311000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	21892000	USD
CY2019	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	864000	USD
CY2018	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	10277000	USD
CY2017	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	20309000	USD
CY2019	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	76181000	USD
CY2018	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	303967000	USD
CY2017	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	16166000	USD
CY2019	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	69389000	USD
CY2018	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	57385000	USD
CY2017	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	0	USD
CY2019	slg	Depreciable Real Estate Reserves Cash Flow Effect DepreciableRealEstateReservesCashFlowEffect	-7047000	USD
CY2018	slg	Depreciable Real Estate Reserves Cash Flow Effect DepreciableRealEstateReservesCashFlowEffect	-227543000	USD
CY2017	slg	Depreciable Real Estate Reserves Cash Flow Effect DepreciableRealEstateReservesCashFlowEffect	-178520000	USD
CY2019	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-16749000	USD
CY2018	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-30757000	USD
CY2017	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	73241000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6839000	USD
CY2017	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	0	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	0	USD
CY2017	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	3262000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-17083000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Straight Line Rent StraightLineRent	13941000	USD
CY2018	us-gaap	Straight Line Rent StraightLineRent	18216000	USD
CY2017	us-gaap	Straight Line Rent StraightLineRent	38009000	USD
CY2019	slg	Non Cash Lease Expense NonCashLeaseExpense	13744000	USD
CY2018	slg	Non Cash Lease Expense NonCashLeaseExpense	2016000	USD
CY2017	slg	Non Cash Lease Expense NonCashLeaseExpense	1020000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-271000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-2932000	USD
CY2017	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-19621000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	4968000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-6968000	USD
CY2018	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	1044000	USD
CY2017	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	7209000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	5717000	USD
CY2019	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	-7802000	USD
CY2019	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	70938000	USD
CY2018	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	44158000	USD
CY2017	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	41939000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	18630000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	8310000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	23068000	USD
CY2019	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	-25597000	USD
CY2018	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	4410000	USD
CY2017	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	-12440000	USD
CY2019	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	10824000	USD
CY2018	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	12348000	USD
CY2017	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	46607000	USD
CY2019	slg	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	-11200000	USD
CY2018	slg	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	0	USD
CY2017	slg	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	0	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	376473000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	441537000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	543001000	USD
CY2019	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	262591000	USD
CY2018	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	60486000	USD
CY2017	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	28680000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	252986000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	254460000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	336001000	USD
CY2019	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	5239000	USD
CY2018	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	0	USD
CY2017	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	0	USD
CY2019	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	128682000	USD
CY2018	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	400429000	USD
CY2017	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	389249000	USD
CY2019	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	79020000	USD
CY2018	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	233118000	USD
CY2017	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	319745000	USD
CY2019	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	208302000	USD
CY2018	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	1231004000	USD
CY2017	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	692796000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	0	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	0	USD
CY2017	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	55129000	USD
CY2019	slg	Payments For Proceeds From Other Investments PaymentsForProceedsFromOtherInvestments	7869000	USD
CY2018	slg	Payments For Proceeds From Other Investments PaymentsForProceedsFromOtherInvestments	38912000	USD
CY2017	slg	Payments For Proceeds From Other Investments PaymentsForProceedsFromOtherInvestments	-25330000	USD
CY2019	slg	Origination Of Debt And Preferred Equity Investments OriginationOfDebtAndPreferredEquityInvestments	607844000	USD
CY2018	slg	Origination Of Debt And Preferred Equity Investments OriginationOfDebtAndPreferredEquityInvestments	731216000	USD
CY2017	slg	Origination Of Debt And Preferred Equity Investments OriginationOfDebtAndPreferredEquityInvestments	1129970000	USD
CY2019	slg	Repayments Or Redemption Of Debt And Preferred Equity Investments RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments	1092383000	USD
CY2018	slg	Repayments Or Redemption Of Debt And Preferred Equity Investments RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments	703043000	USD
CY2017	slg	Repayments Or Redemption Of Debt And Preferred Equity Investments RepaymentsOrRedemptionOfDebtAndPreferredEquityInvestments	812914000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	114494000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	681662000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	22014000	USD
CY2019	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	752984000	USD
CY2018	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	564391000	USD
CY2017	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	870459000	USD
CY2019	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	230076000	USD
CY2018	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	868842000	USD
CY2017	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	902460000	USD
CY2019	us-gaap	Proceeds From Issuance Of Unsecured Debt ProceedsFromIssuanceOfUnsecuredDebt	1310000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Unsecured Debt ProceedsFromIssuanceOfUnsecuredDebt	3120000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Unsecured Debt ProceedsFromIssuanceOfUnsecuredDebt	2784599000	USD
CY2019	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	1570000000	USD
CY2018	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	2560000000	USD
CY2017	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	2276782000	USD
CY2019	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	0	USD
CY2018	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	13918000	USD
CY2017	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	0	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	334000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	29048000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	23537000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	384399000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	979541000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	806302000	USD
CY2019	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	18142000	USD
CY2018	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	1208000	USD
CY2017	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	275000	USD
CY2019	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	27495000	USD
CY2018	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	33972000	USD
CY2017	us-gaap	Payments For Repurchase Of Other Equity PaymentsForRepurchaseOfOtherEquity	0	USD
CY2019	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	478000	USD
CY2018	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	8364000	USD
CY2017	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	52446000	USD
CY2019	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	10239000	USD
CY2018	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	5459000	USD
CY2017	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	36275000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	306386000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	313230000	USD
CY2019	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	25845000	USD
CY2018	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	0	USD
CY2017	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	0	USD
CY2019	slg	Distribution To Noncontrolling Interest Operating Partnership DistributionToNoncontrollingInterestOperatingPartnership	14729000	USD
CY2018	slg	Distribution To Noncontrolling Interest Operating Partnership DistributionToNoncontrollingInterestOperatingPartnership	15000000	USD
CY2017	slg	Distribution To Noncontrolling Interest Operating Partnership DistributionToNoncontrollingInterestOperatingPartnership	14266000	USD
CY2017	us-gaap	Payments Of Dividends PaymentsOfDividends	333543000	USD
CY2019	slg	Proceeds From Participating Mortgage Loan ProceedsFromParticipatingMortgageLoan	0	USD
CY2018	slg	Proceeds From Participating Mortgage Loan ProceedsFromParticipatingMortgageLoan	16000	USD
CY2017	slg	Proceeds From Participating Mortgage Loan ProceedsFromParticipatingMortgageLoan	17227000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3495000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3842000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3879000	USD
CY2019	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	21162000	USD
CY2018	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	15109000	USD
CY2017	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	27100000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-528650000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1094112000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-684956000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-37683000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	29087000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-119941000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	279113000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	250026000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	369967000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	241430000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	279113000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	250026000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	248684000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	259776000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	273819000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	1489000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	1418000	USD
CY2017	us-gaap	Income Taxes Paid IncomeTaxesPaid	2448000	USD
CY2019	us-gaap	Partners Capital Account Sale Of Units PartnersCapitalAccountSaleOfUnits	0	USD
CY2018	us-gaap	Partners Capital Account Sale Of Units PartnersCapitalAccountSaleOfUnits	0	USD
CY2017	us-gaap	Partners Capital Account Sale Of Units PartnersCapitalAccountSaleOfUnits	25723000	USD
CY2019	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	471000	USD
CY2018	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	16303000	USD
CY2017	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	21574000	USD
CY2019	slg	Redemption Of Units In Operating Partnership For Sale Of Joint Venture RedemptionOfUnitsInOperatingPartnershipForSaleOfJointVenture	0	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	6056000	USD
CY2018	slg	Redemption Of Units In Operating Partnership For Sale Of Joint Venture RedemptionOfUnitsInOperatingPartnershipForSaleOfJointVenture	10445000	USD
CY2017	slg	Redemption Of Units In Operating Partnership For Sale Of Joint Venture RedemptionOfUnitsInOperatingPartnershipForSaleOfJointVenture	0	USD
CY2019	us-gaap	Transfer Of Investments TransferOfInvestments	34498000	USD
CY2018	us-gaap	Transfer Of Investments TransferOfInvestments	298956000	USD
CY2017	us-gaap	Transfer Of Investments TransferOfInvestments	0	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	0	USD
CY2017	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	6667000	USD
CY2019	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	34320000	USD
CY2018	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	34236000	USD
CY2017	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	5712000	USD
CY2019	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	395000	USD
CY2018	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	298404000	USD
CY2017	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	695204000	USD
CY2019	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	391664000	USD
CY2018	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	0	USD
CY2017	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	611809000	USD
CY2019	slg	Transfer To Liabilities Related To Net Assets Held For Sale TransferToLiabilitiesRelatedToNetAssetsHeldForSale	0	USD
CY2018	slg	Transfer To Liabilities Related To Net Assets Held For Sale TransferToLiabilitiesRelatedToNetAssetsHeldForSale	0	USD
CY2017	slg	Transfer To Liabilities Related To Net Assets Held For Sale TransferToLiabilitiesRelatedToNetAssetsHeldForSale	5364000	USD
CY2019	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	19577000	USD
CY2018	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	124249000	USD
CY2017	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	15488000	USD
CY2019	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	48223000	USD
CY2018	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	0	USD
CY2017	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	0	USD
CY2019	slg	Share Repurchases Payable ShareRepurchasesPayable	0	USD
CY2018	slg	Share Repurchases Payable ShareRepurchasesPayable	0	USD
CY2017	slg	Share Repurchases Payable ShareRepurchasesPayable	41746000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	389120000	USD
CY2018	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2017	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2019	slg	Common Stock Dividends Per Share Quarterly Distributions CommonStockDividendsPerShareQuarterlyDistributions	0.885
CY2018	slg	Common Stock Dividends Per Share Quarterly Distributions CommonStockDividendsPerShareQuarterlyDistributions	0.85
CY2017	slg	Common Stock Dividends Per Share Quarterly Distributions CommonStockDividendsPerShareQuarterlyDistributions	0.8125
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	166070000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	129475000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	127888000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	75360000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	149638000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	241430000	USD
CY2017Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	122138000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	279113000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	250026000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	848048000	USD
CY2017	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	30203000	USD
CY2019	slg	Common Stock Dividends Per Share Quarterly Distributions CommonStockDividendsPerShareQuarterlyDistributions	0.885
CY2018	slg	Common Stock Dividends Per Share Quarterly Distributions CommonStockDividendsPerShareQuarterlyDistributions	0.85
CY2017	slg	Common Stock Dividends Per Share Quarterly Distributions CommonStockDividendsPerShareQuarterlyDistributions	0.8125
CY2019Q4	us-gaap	Number Of Real Estate Properties NumberOfRealEstateProperties	71	building
CY2019Q4	us-gaap	Area Of Real Estate Property AreaOfRealEstateProperty	27607971	sqft
CY2019Q4	slg	Real Estate Weighted Average Occupancy RealEstateWeightedAverageOccupancy	0.943
CY2019	slg	Number Of Shares On Redemption Of One Unit Of Partnership Interest NumberOfSharesOnRedemptionOfOneUnitOfPartnershipInterest	1	shares
CY2019	slg	Weighted Average Amortization Period Above Market Lease Costs WeightedAverageAmortizationPeriodAboveMarketLeaseCosts	P1Y8M12D
CY2019	slg	Weighted Average Amortization Period Below Market Lease Costs WeightedAverageAmortizationPeriodBelowMarketLeaseCosts	P2Y9M18D
CY2019	slg	Weighted Average Amortization Period In Place Lease Costs WeightedAverageAmortizationPeriodInPlaceLeaseCosts	P3Y6M
CY2019	slg	Period From Cessation Of Major Construction Activity To Completion Of Construction Project Maximum PeriodFromCessationOfMajorConstructionActivityToCompletionOfConstructionProjectMaximum	P1Y
CY2019	slg	Commercial Real Estate Properties Depreciationand Amortization CommercialRealEstatePropertiesDepreciationandAmortization	233500000	USD
CY2018	slg	Commercial Real Estate Properties Depreciationand Amortization CommercialRealEstatePropertiesDepreciationandAmortization	242800000	USD
CY2017	slg	Commercial Real Estate Properties Depreciationand Amortization CommercialRealEstatePropertiesDepreciationandAmortization	365300000	USD
CY2019	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	4500000	USD
CY2018	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	6800000	USD
CY2017	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	20300000	USD
CY2019	slg	Interest Expense Increase Decrease Assumed Above Market Rate Mortgage Amortization InterestExpenseIncreaseDecreaseAssumedAboveMarketRateMortgageAmortization	0	USD
CY2017	slg	Interest Expense Increase Decrease Assumed Above Market Rate Mortgage Amortization InterestExpenseIncreaseDecreaseAssumedAboveMarketRateMortgageAmortization	-800000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	255198000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	266540000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	228223000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	241040000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	26975000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	25500000	USD
CY2019Q4	us-gaap	Below Market Lease Gross BelowMarketLeaseGross	282048000	USD
CY2018Q4	us-gaap	Below Market Lease Gross BelowMarketLeaseGross	276245000	USD
CY2019Q4	us-gaap	Below Market Lease Accumulated Amortization BelowMarketLeaseAccumulatedAmortization	249514000	USD
CY2018Q4	us-gaap	Below Market Lease Accumulated Amortization BelowMarketLeaseAccumulatedAmortization	253767000	USD
CY2019Q4	us-gaap	Below Market Lease Net BelowMarketLeaseNet	32534000	USD
CY2018Q4	us-gaap	Below Market Lease Net BelowMarketLeaseNet	22478000	USD
CY2019Q4	slg	Net Intangible Assets Transferredto Assets Heldfor Sale NetIntangibleAssetsTransferredtoAssetsHeldforSale	0	USD
CY2019Q4	slg	Net Intangible Liabilities Transferredto Liabilities Relatedto Assets Heldfor Sale NetIntangibleLiabilitiesTransferredtoLiabilitiesRelatedtoAssetsHeldforSale	0	USD
CY2018Q4	slg	Net Intangible Assets Transferredto Assets Heldfor Sale NetIntangibleAssetsTransferredtoAssetsHeldforSale	0	USD
CY2018Q4	slg	Net Intangible Liabilities Transferredto Liabilities Relatedto Assets Heldfor Sale NetIntangibleLiabilitiesTransferredtoLiabilitiesRelatedtoAssetsHeldforSale	0	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	55100000	USD
CY2017	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	-3300000	USD
CY2019	slg	Numberof Joint Ventureswith Performance Guaranteesunder Master Leases NumberofJointVentureswithPerformanceGuaranteesunderMasterLeases	1	joint_venture
CY2019	slg	Deferred Lease Costs Capitalized In Period DeferredLeaseCostsCapitalizedInPeriod	6300000	USD
CY2018	slg	Deferred Lease Costs Capitalized In Period DeferredLeaseCostsCapitalizedInPeriod	15700000	USD
CY2017	slg	Deferred Lease Costs Capitalized In Period DeferredLeaseCostsCapitalizedInPeriod	16400000	USD
CY2019	slg	Operating Leases Estimated Average Lease Term OperatingLeasesEstimatedAverageLeaseTerm	P8Y
CY2019	slg	Financing Receivable Number Of Days Past Due For Suspending Income Recognition FinancingReceivableNumberOfDaysPastDueForSuspendingIncomeRecognition	P90D
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1500000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2800000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4300000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	3.40
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	3.25
CY2017	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	3.10
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;padding-bottom:8px;text-align:justify;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-weight:bold;">Use of Estimates</span></div><div style="line-height:120%;padding-bottom:8px;text-align:justify;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.</span></div>
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="line-height:120%;padding-bottom:8px;text-align:justify;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-weight:bold;">Concentrations of Credit Risk</span></div><div style="line-height:120%;padding-bottom:8px;text-align:justify;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash investments, debt and preferred equity investments and accounts receivable. We place our cash investments with high quality financial institutions. The collateral securing our debt and preferred equity investments is located in the New York metropolitan area. See Note 5, "Debt and Preferred Equity Investments." </span></div>We perform ongoing credit evaluations of our tenants and require most tenants to provide security deposits or letters of credit. Though these security deposits and letters of credit are insufficient to meet the total value of a tenant's lease obligation, they are a measure of good faith and a source of funds to offset the economic costs associated with lost revenue and the costs associated with re-tenanting a space. The properties in our real estate portfolio are located in the New York metropolitan area. The tenants located in our buildings operate in various industries.
CY2019	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="line-height:120%;padding-bottom:8px;text-align:justify;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-weight:bold;">Reclassification</span></div><div style="line-height:120%;padding-bottom:8px;text-align:justify;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Certain prior year balances have been reclassified to conform to our current year presentation.</span></div>
CY2018Q4	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	2099393000	USD
CY2017Q4	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	2114041000	USD
CY2019	us-gaap	Mortgage Loans On Real Estate Amortization Of Premium MortgageLoansOnRealEstateAmortizationOfPremium	1190689000	USD
CY2018	us-gaap	Mortgage Loans On Real Estate Amortization Of Premium MortgageLoansOnRealEstateAmortizationOfPremium	994906000	USD
CY2019	slg	Sec Schedule1229 Real Estate Companies Investment In Mortgage Loans On Real Estate Loan Loss Reserve Period Increase Decrease SECSchedule1229RealEstateCompaniesInvestmentInMortgageLoansOnRealEstateLoanLossReservePeriodIncreaseDecrease	4000000	USD
CY2018	slg	Sec Schedule1229 Real Estate Companies Investment In Mortgage Loans On Real Estate Loan Loss Reserve Period Increase Decrease SECSchedule1229RealEstateCompaniesInvestmentInMortgageLoansOnRealEstateLoanLossReservePeriodIncreaseDecrease	-5750000	USD
CY2019Q4	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	1580306000	USD
CY2018Q4	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	2099393000	USD
CY2019Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	1580306000	USD
CY2019Q4	slg	Mortgage Loanson Real Estate Senior Financing MortgageLoansonRealEstateSeniorFinancing	5560939000	USD
CY2018Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	5750000	USD
CY2017Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	0	USD
CY2016Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	0	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6839000	USD
CY2017	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	0	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	0	USD
CY2017	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	0	USD
CY2019	slg	Financing Receivable Allowance For Credit Losses Write Offs And Reclassifications FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications	4000000	USD
CY2018	slg	Financing Receivable Allowance For Credit Losses Write Offs And Reclassifications FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications	1089000	USD
CY2017	slg	Financing Receivable Allowance For Credit Losses Write Offs And Reclassifications FinancingReceivableAllowanceForCreditLossesWriteOffsAndReclassifications	0	USD
CY2019Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	1750000	USD
CY2018Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	5750000	USD
CY2017Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	0	USD
CY2019Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	1800000	USD
CY2019Q4	slg	Financing Receivable Number Ofinvestments Marketed For Sale FinancingReceivableNumberOfinvestmentsMarketedForSale	1	loan
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	142900000	USD
CY2018Q4	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	5800000	USD
CY2018Q4	slg	Financing Receivable Number Ofinvestments Marketed For Sale FinancingReceivableNumberOfinvestmentsMarketedForSale	2	loan
CY2018Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	159900000	USD
CY2019	slg	Financing Receivable Portfolio Segments Number FinancingReceivablePortfolioSegmentsNumber	1	segment
CY2019Q4	slg	Financing Receivable Recorded In Other Assets FinancingReceivableRecordedInOtherAssets	131100000	USD
CY2018Q4	slg	Financing Receivable Recorded In Other Assets FinancingReceivableRecordedInOtherAssets	124500000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	28400000	USD
CY2019Q4	slg	Debt And Equity Securities Weighted Average Risk Rating DebtAndEquitySecuritiesWeightedAverageRiskRating	1.2
CY2019	srt	Mortgage Loans On Real Estate Interest Rate MortgageLoansOnRealEstateInterestRate	0.0842
CY2019Q4	us-gaap	Variable Interest Entity Nonconsolidated Carrying Amount Assets And Liabilities Net VariableInterestEntityNonconsolidatedCarryingAmountAssetsAndLiabilitiesNet	145900000	USD
CY2018Q4	us-gaap	Variable Interest Entity Nonconsolidated Carrying Amount Assets And Liabilities Net VariableInterestEntityNonconsolidatedCarryingAmountAssetsAndLiabilitiesNet	808300000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	4000000.0	USD
CY2018Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	11700000	USD
CY2017Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	0	USD
CY2018Q4	us-gaap	Equity Method Investments EquityMethodInvestments	3019020000	USD
CY2019Q4	us-gaap	Equity Method Investment Difference Between Carrying Amount And Underlying Equity EquityMethodInvestmentDifferenceBetweenCarryingAmountAndUnderlyingEquity	133100000	USD
CY2019Q4	us-gaap	Deferred Costs Leasing Gross DeferredCostsLeasingGross	466136000	USD
CY2018Q4	us-gaap	Deferred Costs Leasing Gross DeferredCostsLeasingGross	453833000	USD
CY2019Q4	us-gaap	Deferred Costs Leasing Accumulated Amortization DeferredCostsLeasingAccumulatedAmortization	260853000	USD
CY2018Q4	us-gaap	Deferred Costs Leasing Accumulated Amortization DeferredCostsLeasingAccumulatedAmortization	244723000	USD
CY2019Q4	us-gaap	Deferred Costs Leasing Net DeferredCostsLeasingNet	205283000	USD
CY2018Q4	us-gaap	Deferred Costs Leasing Net DeferredCostsLeasingNet	209110000	USD
CY2019Q4	slg	Secured Debt Bearing Fixed Interest Amount SecuredDebtBearingFixedInterestAmount	1383449000	USD
CY2018Q4	slg	Secured Debt Bearing Fixed Interest Amount SecuredDebtBearingFixedInterestAmount	1389717000	USD
CY2019Q4	slg	Secured Debt Bearing Variable Interest Amount SecuredDebtBearingVariableInterestAmount	828434000	USD
CY2018Q4	slg	Secured Debt Bearing Variable Interest Amount SecuredDebtBearingVariableInterestAmount	598442000	USD
CY2019Q4	slg	Secured Debt Gross SecuredDebtGross	2211883000	USD
CY2018Q4	slg	Secured Debt Gross SecuredDebtGross	1988159000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	28630000	USD
CY2018Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	26919000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	2183253000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	1961240000	USD
CY2019Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	3300000000	USD
CY2018Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	2600000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	468824000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	601546000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	1338805000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	1597301000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	478781000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1066626000	USD
CY2019Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	5551883000	USD
CY2019	us-gaap	Interest Costs Incurred InterestCostsIncurred	246848000	USD
CY2018	us-gaap	Interest Costs Incurred InterestCostsIncurred	236719000	USD
CY2017	us-gaap	Interest Costs Incurred InterestCostsIncurred	281551000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3243000	USD
CY2018	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	8069000	USD
CY2017	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3098000	USD
CY2019	us-gaap	Interest Costs Capitalized Adjustment InterestCostsCapitalizedAdjustment	55446000	USD
CY2018	us-gaap	Interest Costs Capitalized Adjustment InterestCostsCapitalizedAdjustment	34162000	USD
CY2017	us-gaap	Interest Costs Capitalized Adjustment InterestCostsCapitalizedAdjustment	26020000	USD
CY2019	us-gaap	Interest Income Operating InterestIncomeOperating	4124000	USD
CY2018	us-gaap	Interest Income Operating InterestIncomeOperating	1957000	USD
CY2017	us-gaap	Interest Income Operating InterestIncomeOperating	1584000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	190521000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	208669000	USD
CY2017	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	257045000	USD
CY2019Q4	us-gaap	Due From Joint Ventures DueFromJointVentures	9352000	USD
CY2018Q4	us-gaap	Due From Joint Ventures DueFromJointVentures	18655000	USD
CY2019Q4	us-gaap	Due From Other Related Parties DueFromOtherRelatedParties	11769000	USD
CY2018Q4	us-gaap	Due From Other Related Parties DueFromOtherRelatedParties	9378000	USD
CY2019Q4	us-gaap	Due From Related Parties DueFromRelatedParties	21121000	USD
CY2018Q4	us-gaap	Due From Related Parties DueFromRelatedParties	28033000	USD
CY2019	slg	Preferred Stock Convertible Conversion Ratio PreferredStockConvertibleConversionRatio	6.71348
CY2019Q4	slg	Total Shares Authorized TotalSharesAuthorized	260000000	shares
CY2019Q4	slg	Total Par Or Stated Value Per Share TotalParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	160000000	shares
CY2019Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Excess Stock Shares Authorized ExcessStockSharesAuthorized	75000000	shares
CY2019Q4	slg	Excess Stock Par Or Stated Value Per Share ExcessStockParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	25000000	shares
CY2019Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Excess Stock Shares Issued ExcessStockSharesIssued	0	shares
CY2017	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	8342411	shares
CY2017	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	101.64
CY2018	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	9744911	shares
CY2018	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	96.22
CY2019	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	83.62
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	4596171	shares
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	255484000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	232312000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	86424000	USD
CY2019	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	253745000	USD
CY2018	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	231760000	USD
CY2017	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	85953000	USD
CY2019	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	-1719000	USD
CY2018	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	-552000	USD
CY2017	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	-471000	USD
CY2019	us-gaap	Dilutive Securities Effect On Basic Earnings Per Share Other DilutiveSecuritiesEffectOnBasicEarningsPerShareOther	13301000	USD
CY2018	us-gaap	Dilutive Securities Effect On Basic Earnings Per Share Other DilutiveSecuritiesEffectOnBasicEarningsPerShareOther	12216000	USD
CY2017	us-gaap	Dilutive Securities Effect On Basic Earnings Per Share Other DilutiveSecuritiesEffectOnBasicEarningsPerShareOther	3995000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	268765000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	244528000	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	90419000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	81733000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	86753000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	98571000	shares
CY2019	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4275000	shares
CY2018	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4562000	shares
CY2017	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4556000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	554000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	215000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	276000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	86562000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	91530000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	103403000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1252670	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1138647	shares
CY2017	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	774782	shares
CY2019	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	2100000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	6300000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	7200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-2733000	USD
CY2017	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	800000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-2304000	USD
CY2018	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1192000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-43495000	USD
CY2019	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	98000	USD
CY2019Q4	slg	Other Comprehensive Income Loss Deferred Net Lossfrom Terminated Hedges OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges	-700000	USD
CY2018Q4	slg	Other Comprehensive Income Loss Deferred Net Lossfrom Terminated Hedges OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges	1300000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	29887000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	4419000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	28638000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	18676000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	221900000	USD
CY2019Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	1580306000	USD
CY2019	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-100000	USD
CY2018	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-200000	USD
CY2017	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-500000	USD
CY2019Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	29500000	USD
CY2019Q4	us-gaap	Assets Needed For Immediate Settlement Aggregate Fair Value AssetsNeededForImmediateSettlementAggregateFairValue	30100000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-44229000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-4072000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-2482000	USD
CY2019	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	5000	USD
CY2018	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-2265000	USD
CY2017	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-2796000	USD
CY2019	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	858587000	USD
CY2018	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	858160000	USD
CY2019	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	120496000	USD
CY2018	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	113596000	USD
CY2019	slg	Operating Lease Lease Income Fixed And Variable Lease Payments OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments	979083000	USD
CY2018	slg	Operating Lease Lease Income Fixed And Variable Lease Payments OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments	971756000	USD
CY2019	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	4474000	USD
CY2018	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	6818000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	983557000	USD
CY2018	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	978574000	USD
CY2019	us-gaap	Multiemployer Plans Plan Contributions1 MultiemployerPlansPlanContributions1	14160000	USD
CY2018	us-gaap	Multiemployer Plans Plan Contributions1 MultiemployerPlansPlanContributions1	13433000	USD
CY2017	us-gaap	Multiemployer Plans Plan Contributions1 MultiemployerPlansPlanContributions1	16745000	USD
CY2019	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	0.15
CY2019	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent Of Match DefinedContributionPlanEmployerMatchingContributionPercentOfMatch	1
CY2019	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.04
CY2017	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent Of Match DefinedContributionPlanEmployerMatchingContributionPercentOfMatch	0.50
CY2017	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.06
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	27243000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2819000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	27263000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1600000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1100000	USD
CY2017	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1000000.0	USD
CY2019Q4	slg	Employment Agreements Minimum Cash Based Compensation In Next Fiscal Year EmploymentAgreementsMinimumCashBasedCompensationInNextFiscalYear	3300000	USD
CY2019	slg	Operating Leases Minimum Lease Term OperatingLeasesMinimumLeaseTerm	P1Y
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	2619000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	31508000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	2794000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	31702000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	2794000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	29548000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	2794000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	814283000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	649289000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	828103000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	796553000	USD
CY2019Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	783655000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	414882000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	44448000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	381671000	USD
CY2019Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	1600000000	USD
CY2019	slg	Finance Lease Cost FinanceLeaseCost	4500000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3200000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	1200000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	33200000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0849
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P67Y
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2019	us-gaap	Revenues Revenues	1238995000	USD
CY2018	us-gaap	Revenues Revenues	1227392000	USD
CY2017	us-gaap	Revenues Revenues	1511473000	USD
CY2019	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	291487000	USD
CY2018	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	270856000	USD
CY2017	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	101069000	USD
CY2019Q4	us-gaap	Assets Assets	12766320000	USD
CY2018Q4	us-gaap	Assets Assets	12751358000	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	100900000	USD
CY2018	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	92600000	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	100500000	USD
CY2019Q4	us-gaap	Revenues Revenues	308082000	USD
CY2019Q3	us-gaap	Revenues Revenues	313634000	USD
CY2019Q2	us-gaap	Revenues Revenues	313024000	USD
CY2019Q1	us-gaap	Revenues Revenues	304255000	USD
CY2019Q4	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	252712000	USD
CY2019Q3	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	263341000	USD
CY2019Q2	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	258383000	USD
CY2019Q1	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	260328000	USD
CY2019Q4	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-11874000	USD
CY2019Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-9864000	USD
CY2019Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-7546000	USD
CY2019Q1	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-5234000	USD
CY2019Q4	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	USD
CY2019Q3	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	USD
CY2019Q2	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	59015000	USD
CY2019Q1	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	17166000	USD
CY2019Q4	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	0	USD
CY2019Q3	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	3799000	USD
CY2019Q2	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	67631000	USD
CY2019Q1	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	-2041000	USD
CY2019Q4	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-19241000	USD
CY2019Q3	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	3541000	USD
CY2019Q2	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	0	USD
CY2019Q1	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-1049000	USD
CY2019Q4	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	0	USD
CY2019Q3	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-7047000	USD
CY2019Q2	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	0	USD
CY2019Q1	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	0	USD
CY2019Q4	slg	Distributions Preferred Units DistributionsPreferredUnits	3086000	USD
CY2019Q3	slg	Distributions Preferred Units DistributionsPreferredUnits	3827000	USD
CY2019Q2	slg	Distributions Preferred Units DistributionsPreferredUnits	8901000	USD
CY2019Q1	slg	Distributions Preferred Units DistributionsPreferredUnits	5239000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	21169000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	36895000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	164840000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	47530000	USD
CY2019Q4	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2019Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2019Q2	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2019Q1	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2019Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	17432000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	33157000	USD
CY2019Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	161103000	USD
CY2019Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	43792000	USD
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.21
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.40
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.94
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.52
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.21
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.40
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.94
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.52
CY2018Q4	us-gaap	Revenues Revenues	317036000	USD
CY2018Q1	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	0	USD
CY2018Q4	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-14889000	USD
CY2018Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-2194000	USD
CY2018Q2	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018Q1	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018Q4	slg	Distributions Preferred Units DistributionsPreferredUnits	-838000	USD
CY2018Q3	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	-3057000	USD
CY2018Q2	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	11149000	USD
CY2018Q1	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	49293000	USD
CY2018Q4	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-36984000	USD
CY2018Q3	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-2504000	USD
CY2018Q2	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-14790000	USD
CY2018Q1	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	23521000	USD
CY2018Q4	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-220852000	USD
CY2018Q3	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-6691000	USD
CY2018Q2	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	0	USD
CY2018Q3	us-gaap	Revenues Revenues	307545000	USD
CY2018Q2	us-gaap	Revenues Revenues	301116000	USD
CY2018Q1	us-gaap	Revenues Revenues	301695000	USD
CY2018Q4	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	267678000	USD
CY2018Q3	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	265553000	USD
CY2018Q2	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	258303000	USD
CY2018Q1	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	258282000	USD
CY2018Q4	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-2398000	USD
CY2018Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	971000	USD
CY2018Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	4702000	USD
CY2018Q1	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	4036000	USD
CY2018Q4	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	167445000	USD
CY2018Q3	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	70937000	USD
CY2018Q2	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	72025000	USD
CY2018Q1	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	-6440000	USD
CY2018Q4	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	0	USD
CY2018Q3	slg	Distributions Preferred Units DistributionsPreferredUnits	7507000	USD
CY2018Q2	slg	Distributions Preferred Units DistributionsPreferredUnits	8606000	USD
CY2018Q1	slg	Distributions Preferred Units DistributionsPreferredUnits	8319000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	-57482000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	91947000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	107293000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	105504000	USD
CY2018Q4	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2018Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2018Q2	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2018Q1	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2018Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-61219000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	88209000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	103556000	USD
CY2018Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	101766000	USD
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.73
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.03
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.19
CY2019	us-gaap	Real Estate Other Acquisitions RealEstateOtherAcquisitions	0	USD
CY2018	us-gaap	Real Estate Other Acquisitions RealEstateOtherAcquisitions	52939000	USD
CY2017	us-gaap	Real Estate Other Acquisitions RealEstateOtherAcquisitions	13323000	USD
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.12
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.73
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.03
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.19
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.12
CY2019Q4	srt	Real Estate And Accumulated Depreciation Amount Of Encumbrances RealEstateAndAccumulatedDepreciationAmountOfEncumbrances	2019700000	USD
CY2019Q4	us-gaap	Real Estate And Accumulated Depreciation Initial Cost Of Land RealEstateAndAccumulatedDepreciationInitialCostOfLand	1596948000	USD
CY2019Q4	us-gaap	Real Estate And Accumulated Depreciation Initial Cost Of Buildings And Improvements RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements	6033164000	USD
CY2019Q4	slg	Real Estate And Accumulated Depreciation Costs Capitalized Subsequent To Acquisition Of Land RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionOfLand	154596000	USD
CY2019Q4	slg	Real Estate And Accumulated Depreciation Costs Capitalized Subsequent To Acquisition Of Building And Improvements RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionOfBuildingAndImprovements	999859000	USD
CY2019Q4	us-gaap	Real Estate And Accumulated Depreciation Carrying Amount Of Land RealEstateAndAccumulatedDepreciationCarryingAmountOfLand	1751544000	USD
CY2019Q4	us-gaap	Real Estate And Accumulated Depreciation Carrying Amount Of Buildings And Improvements RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements	7033023000	USD
CY2019Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	8784567000	USD
CY2019Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2060560000	USD
CY2018Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	8513935000	USD
CY2017Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	10206122000	USD
CY2016Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	12743332000	USD
CY2019	us-gaap	Real Estate Improvements RealEstateImprovements	251674000	USD
CY2018	us-gaap	Real Estate Improvements RealEstateImprovements	267726000	USD
CY2017	us-gaap	Real Estate Improvements RealEstateImprovements	342014000	USD
CY2019	slg	Real Estate Cost Of Real Estate Sold Retired Or Deconsolidated RealEstateCostOfRealEstateSoldRetiredOrDeconsolidated	-18958000	USD
CY2018	slg	Real Estate Cost Of Real Estate Sold Retired Or Deconsolidated RealEstateCostOfRealEstateSoldRetiredOrDeconsolidated	2012852000	USD
CY2017	slg	Real Estate Cost Of Real Estate Sold Retired Or Deconsolidated RealEstateCostOfRealEstateSoldRetiredOrDeconsolidated	2892547000	USD
CY2019Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	8784567000	USD
CY2018Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	8513935000	USD
CY2017Q4	us-gaap	Real Estate Gross At Carrying Value RealEstateGrossAtCarryingValue	10206122000	USD
CY2019Q4	srt	Real Estate Federal Income Tax Basis RealEstateFederalIncomeTaxBasis	10300000000	USD
CY2018Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2099137000	USD
CY2017Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2300116000	USD
CY2016Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2264694000	USD
CY2019	us-gaap	Sec Schedule Iii Real Estate Accumulated Depreciation Depreciation Expense SECScheduleIIIRealEstateAccumulatedDepreciationDepreciationExpense	222867000	USD
CY2018	us-gaap	Sec Schedule Iii Real Estate Accumulated Depreciation Depreciation Expense SECScheduleIIIRealEstateAccumulatedDepreciationDepreciationExpense	245033000	USD
CY2017	us-gaap	Sec Schedule Iii Real Estate Accumulated Depreciation Depreciation Expense SECScheduleIIIRealEstateAccumulatedDepreciationDepreciationExpense	347015000	USD
CY2019	slg	Real Estate Accumulated Depreciation Real Estate Sold Retired Or Deconsolidated RealEstateAccumulatedDepreciationRealEstateSoldRetiredOrDeconsolidated	261444000	USD
CY2018	slg	Real Estate Accumulated Depreciation Real Estate Sold Retired Or Deconsolidated RealEstateAccumulatedDepreciationRealEstateSoldRetiredOrDeconsolidated	446012000	USD
CY2017	slg	Real Estate Accumulated Depreciation Real Estate Sold Retired Or Deconsolidated RealEstateAccumulatedDepreciationRealEstateSoldRetiredOrDeconsolidated	311593000	USD
CY2019Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2060560000	USD
CY2018Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2099137000	USD
CY2017Q4	us-gaap	Real Estate Accumulated Depreciation RealEstateAccumulatedDepreciation	2300116000	USD

Files In Submission

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$SLG
SL Green Realty Corp Stock $slg

2019 Q4 Form 10-K Financial Statement

#000104097120000006 Filed on February 28, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SLG SL Green Realty Corp Stock $slg

2019 Q4 Form 10-K Financial Statement

#000104097120000006 Filed on February 28, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SLG
SL Green Realty Corp Stock $slg