$SLG
SL GREEN REALTY CORP Stock $slg

$slg Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-Q Financial Statement

#000104097119000031 Filed on November 06, 2019

Income Statement

Concept	2019 Q4	2019 Q3	2018 Q3
Revenue	$308.1M	$313.6M	$307.5M
YoY Change	-2.82%	1.98%	-17.9%
Cost Of Revenue	$114.9M	$117.8M	$115.2M
YoY Change	5.12%	2.26%	-22.37%
Gross Profit	$193.2M	$195.9M	$192.4M
YoY Change	-6.98%	1.82%	-14.94%
Gross Profit Margin	62.71%	62.46%	62.56%
Selling, General & Admin	$25.90M	$23.80M	$20.60M
YoY Change	-2.26%	15.53%	-14.03%
% of Gross Profit	13.41%	12.15%	10.71%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$67.20M	$73.50M	$73.40M
YoY Change	-9.31%	0.14%	-23.3%
% of Gross Profit	34.78%	37.52%	38.15%
Operating Expenses	$90.00M	$23.80M	$20.60M
YoY Change	-13.21%	15.53%	-14.03%
Operating Profit	$103.2M	$172.1M	$171.8M
YoY Change	-0.77%	0.17%	-15.05%
Interest Expense	-$59.70M	$63.61M	$64.08M
YoY Change	-154.08%	-0.74%	-12.05%
% of Operating Profit	-57.85%	36.96%	37.3%
Other Income/Expense, Net	$0.00	-$7.000M	-$6.700M
YoY Change	-100.0%	4.48%
Pretax Income	$24.30M	$40.70M	$99.50M
YoY Change	-141.68%	-59.1%	144.55%
Income Tax		-$1.000M	$300.0K
% Of Pretax Income		-2.46%	0.3%
Net Earnings	$21.17M	$36.90M	$91.95M
YoY Change	-136.83%	-59.87%	115.8%
Net Earnings / Revenue	6.87%	11.76%	29.9%
Basic Earnings Per Share	$0.21	$0.40	$1.03
Diluted Earnings Per Share	$0.21	$0.40	$1.03
COMMON SHARES
Basic Shares Outstanding	80.11M shares	82.29M shares	85.57M shares
Diluted Shares Outstanding		86.71M shares	90.43M shares

Balance Sheet

Concept	2019 Q4	2019 Q3	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$196.0M	$152.0M	$188.8M
YoY Change	23.93%	-19.51%	-30.15%
Cash & Equivalents	$166.1M	$121.8M	$160.2M
Short-Term Investments	$29.89M	$30.21M	$28.54M
Other Short-Term Assets
YoY Change
Inventory	$392.0M	$403.0M	$696.0M
Prepaid Expenses
Receivables	$348.0M	$371.0M	$395.0M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$906.0M	$896.0M	$1.251B
YoY Change	69.35%	-28.38%	48.57%
LONG-TERM ASSETS
Property, Plant & Equipment	$6.724B	$6.941B	$6.525B
YoY Change	4.82%	6.38%	-30.75%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$2.913B	$2.924B	$3.071B
YoY Change	-3.52%	-4.79%	50.1%
Other Assets	$281.0M	$277.0M	$301.0M
YoY Change	-21.73%	-7.97%	-15.45%
Total Long-Term Assets	$11.86B	$12.40B	$12.20B
YoY Change	-2.91%	1.6%	-14.47%
TOTAL ASSETS
Total Short-Term Assets	$906.0M	$896.0M	$1.251B
Total Long-Term Assets	$11.86B	$12.40B	$12.20B
Total Assets	$12.77B	$13.29B	$13.46B
YoY Change	0.12%	-1.19%	-10.95%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$167.0M	$143.0M	$141.0M
YoY Change	13.61%	1.42%	-2.76%
Accrued Expenses	$404.0M	$412.0M	$27.00M
YoY Change	1396.3%	1425.93%	-20.59%
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	$696.0M	$315.0M
YoY Change	123.51%	120.95%	-6.25%
LONG-TERM LIABILITIES
Long-Term Debt	$5.553B	$5.880B	$5.584B
YoY Change	-0.57%	5.3%	-13.67%
Other Long-Term Liabilities	$291.0M	$267.0M	$519.0M
YoY Change	37.91%	-48.55%	48.29%
Total Long-Term Liabilities	$5.844B	$6.147B	$6.103B
YoY Change	0.83%	0.72%	-10.49%
TOTAL LIABILITIES
Total Short-Term Liabilities	$713.0M	$696.0M	$315.0M
Total Long-Term Liabilities	$5.844B	$6.147B	$6.103B
Total Liabilities	$6.556B	$6.844B	$6.419B
YoY Change	7.21%	6.62%	-10.26%
SHAREHOLDERS EQUITY
Retained Earnings	$1.085B	$1.226B	$1.477B
YoY Change	-15.19%	-17.0%	4.72%
Common Stock	$803.0K	$826.0K	$867.0K
YoY Change	-5.19%	-4.73%	-11.98%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$124.0M	$124.0M	$124.0M
YoY Change	0.0%	0.0%	0.0%
Treasury Stock Shares	1.026M shares	1.055M shares	1.055M shares
Shareholders Equity	$5.441B	$5.692B	$6.215B
YoY Change
Total Liabilities & Shareholders Equity	$12.77B	$13.29B	$13.46B
YoY Change	0.12%	-1.19%	-10.95%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2018 Q3
OPERATING ACTIVITIES
Net Income	$21.17M	$36.90M	$91.95M
YoY Change	-136.83%	-59.87%	115.8%
Depreciation, Depletion And Amortization	$67.20M	$73.50M	$73.40M
YoY Change	-9.31%	0.14%	-23.3%
Cash From Operating Activities	$77.10M	$81.50M	$71.30M
YoY Change	-37.82%	14.31%	-29.68%
INVESTING ACTIVITIES
Capital Expenditures	-$103.3M	-$56.90M	-$97.70M
YoY Change	-6.85%	-41.76%	-12.53%
Acquisitions
YoY Change
Other Investing Activities	$458.7M	$282.4M	$329.9M
YoY Change	56.93%	-14.4%	20.49%
Cash From Investing Activities	$355.4M	$225.5M	$232.1M
YoY Change	95.81%	-2.84%	43.27%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-407.6M	-331.6M	-424.9M
YoY Change	43.07%	-21.96%	43.99%
NET CHANGE
Cash From Operating Activities	77.10M	81.50M	71.30M
Cash From Investing Activities	355.4M	225.5M	232.1M
Cash From Financing Activities	-407.6M	-331.6M	-424.9M
Net Change In Cash	24.90M	-24.60M	-121.5M
YoY Change	20.87%	-79.75%	283.28%
FREE CASH FLOW
Cash From Operating Activities	$77.10M	$81.50M	$71.30M
Capital Expenditures	-$103.3M	-$56.90M	-$97.70M
Free Cash Flow	$180.4M	$138.4M	$169.0M
YoY Change	-23.2%	-18.11%	-20.69%

Facts In Submission

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	dei	Amendment Flag AmendmentFlag	false
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Entity Central Index Key EntityCentralIndexKey	0001040971
	dei	Entity Small Business EntitySmallBusiness	false
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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	1-13199
	dei	Entity Registrant Name EntityRegistrantName	SL GREEN REALTY CORP
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MD
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	13-3956775
	dei	Entity Address Address Line1 EntityAddressAddressLine1	420 Lexington Avenue
	dei	Entity Address City Or Town EntityAddressCityOrTown	New York
	dei	Entity Address State Or Province EntityAddressStateOrProvince	NY
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	10170
	dei	City Area Code CityAreaCode	212
	dei	Local Phone Number LocalPhoneNumber	594-2700
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
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CY2019Q3	slg	Transaction Related Costs TransactionRelatedCosts	44000	USD
CY2018Q3	slg	Transaction Related Costs TransactionRelatedCosts	163000	USD
	slg	Transaction Related Costs TransactionRelatedCosts	360000	USD
	slg	Transaction Related Costs TransactionRelatedCosts	673000	USD
CY2019Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	23841000	USD
CY2018Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	20594000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	75300000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	66601000	USD
CY2019Q3	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	263341000	USD
CY2018Q3	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	265553000	USD
	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	782052000	USD
	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	782138000	USD
CY2019Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-9864000	USD
CY2018Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	971000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-22644000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	9709000	USD
CY2019Q3	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	USD
CY2018Q3	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	70937000	USD
	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	76181000	USD
	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	136522000	USD
CY2019Q3	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	3799000	USD
CY2018Q3	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	-3057000	USD
	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	69389000	USD
	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	57385000	USD
CY2019Q3	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	3541000	USD
CY2018Q3	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	-2504000	USD
	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	2492000	USD
	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	6227000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-2524000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	234000	USD
CY2019Q3	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-624000	USD
CY2018Q3	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-136000	USD
CY2019Q3	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-7047000	USD
CY2018Q3	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-6691000	USD
	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-7047000	USD
	slg	Depreciable Real Estate Reserves Effecton Earnings DepreciableRealEstateReservesEffectonEarnings	-6691000	USD
CY2019Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2018Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-2194000	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-2194000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	40722000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	99454000	USD
	us-gaap	Profit Loss ProfitLoss	267232000	USD
	us-gaap	Profit Loss ProfitLoss	329176000	USD
CY2019Q3	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	1719000	USD
CY2018Q3	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	4797000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	12306000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	15656000	USD
CY2019Q3	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	2732000	USD
CY2018Q3	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	2846000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	8185000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	8542000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	36895000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	91947000	USD
	us-gaap	Net Income Loss NetIncomeLoss	249265000	USD
	us-gaap	Net Income Loss NetIncomeLoss	304744000	USD
CY2019Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2018Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	11213000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	11213000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	33157000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	88209000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	238052000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	293531000	USD
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.40
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.03
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.87
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.34
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.40
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.03
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.87
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.34
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	82292000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	85566000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	82855000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	87692000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	86714000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	90428000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	87309000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	92580000	shares
CY2019Q3	us-gaap	Profit Loss ProfitLoss	40722000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	99454000	USD
	us-gaap	Profit Loss ProfitLoss	267232000	USD
	us-gaap	Profit Loss ProfitLoss	329176000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-12574000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	3919000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-59680000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	18809000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	230000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-32000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	1571000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-39000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-12344000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3887000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-58109000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	18770000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	28378000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	103341000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	209123000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	347946000	USD
CY2019Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3827000	USD
CY2018Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	7507000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	17967000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	24432000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-607000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	210000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-2869000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	1075000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	25158000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	95624000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	194025000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	322439000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5947855000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	39000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-11737000	USD
CY2019Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	25000	USD
	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	210470000	USD
	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	25791000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-43503000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	7475000	USD
	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	263000	USD
	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	446000	USD
	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	-14028000	USD
	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-10533000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	109313000	USD
	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	50692000	USD
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	271000	USD
	us-gaap	Dividends Common Stock DividendsCommonStock	140377000	USD
CY2019Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5879501000	USD
CY2019Q3	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	36271000	USD
CY2019Q3	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	54000	USD
CY2019Q3	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	-1481000	USD
CY2019Q3	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-5948000	USD
CY2019Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	74531000	USD
CY2019Q3	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	2404000	USD
CY2019Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	207000	USD
CY2019Q3	us-gaap	Dividends Common Stock DividendsCommonStock	69140000	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5763300000	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
	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	213168000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	14018000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	7475000	USD
	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	64000	USD
	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	1560000	USD
	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	-4493000	USD
	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-8090000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	693091000	USD
	slg	Common Stock Issued During Period Value New Issues CommonStockIssuedDuringPeriodValueNewIssues	5637000	USD
	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	1828000	USD
	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	314596000	USD
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	724000	USD
	us-gaap	Dividends Common Stock DividendsCommonStock	141908000	USD
CY2018Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6242056000	USD
CY2018Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	1139000	USD
CY2018Q3	us-gaap	Dividends Common Stock DividendsCommonStock	69371000	USD
CY2018Q3	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	91811000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	3677000	USD
CY2018Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	52000	USD
CY2018Q3	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	0	USD
CY2018Q3	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	11941000	USD
CY2018Q3	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-4634000	USD
CY2018Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	25236000	USD
CY2018Q3	slg	Common Stock Issued During Period Value New Issues CommonStockIssuedDuringPeriodValueNewIssues	9936000	USD
CY2018Q3	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	3072000	USD
CY2018Q3	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	520000	USD
CY2018Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6267175000	USD
	us-gaap	Profit Loss ProfitLoss	267232000	USD
	us-gaap	Profit Loss ProfitLoss	329176000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	216834000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	217762000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-22644000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	9709000	USD
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	648000	USD
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	10174000	USD
	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	76181000	USD
	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	136522000	USD
	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	69389000	USD
	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	57385000	USD
	slg	Depreciable Real Estate Reserves Cash Flow Effect DepreciableRealEstateReservesCashFlowEffect	-7047000	USD
	slg	Depreciable Real Estate Reserves Cash Flow Effect DepreciableRealEstateReservesCashFlowEffect	-6691000	USD
	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	2492000	USD
	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	6227000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	0	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	1087000	USD
	slg	Gains Losses On Extinguishment Of Debt Cash Flow Effect GainsLossesOnExtinguishmentOfDebtCashFlowEffect	0	USD
	slg	Gains Losses On Extinguishment Of Debt Cash Flow Effect GainsLossesOnExtinguishmentOfDebtCashFlowEffect	-2194000	USD
	us-gaap	Straight Line Rent StraightLineRent	10005000	USD
	us-gaap	Straight Line Rent StraightLineRent	11328000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	9573000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-8907000	USD
	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	7564000	USD
	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-3186000	USD
	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	-8921000	USD
	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	-5186000	USD
	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	38542000	USD
	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	20715000	USD
	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	18255000	USD
	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	17638000	USD
	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	40279000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	299433000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	317545000	USD
	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	261596000	USD
	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	31828000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	47139000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	52172000	USD
	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	18737000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	150742000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	163750000	USD
	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	228000	USD
	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	0	USD
	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	114050000	USD
	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	298836000	USD
	slg	Proceeds From Equity Method Investment Dividends Or Distributions ProceedsFromEquityMethodInvestmentDividendsOrDistributions	62576000	USD
	slg	Proceeds From Equity Method Investment Dividends Or Distributions ProceedsFromEquityMethodInvestmentDividendsOrDistributions	208724000	USD
	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	138948000	USD
	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	892350000	USD
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	2491000	USD
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	-991000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	555951000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	652309000	USD
	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	642634000	USD
	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	553341000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-240900000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	500232000	USD
	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	699072000	USD
	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	339125000	USD
	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	162024000	USD
	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	351080000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	1090000000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	2205000000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1255000000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	2000000000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	302000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	15689000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	175005000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	760073000	USD
	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	15142000	USD
	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	350000	USD
	slg	Payments For Repurchase Of Partnership Units PaymentsForRepurchaseOfPartnershipUnits	15918000	USD
	slg	Payments For Repurchase Of Partnership Units PaymentsForRepurchaseOfPartnershipUnits	0	USD
	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	478000	USD
	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	1863000	USD
	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	4873000	USD
	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	4900000	USD
	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	25791000	USD
	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	0	USD
	slg	Distribution To Noncontrolling Interest Operating Partnership DistributionToNoncontrollingInterestOperatingPartnership	10993000	USD
	slg	Distribution To Noncontrolling Interest Operating Partnership DistributionToNoncontrollingInterestOperatingPartnership	11469000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	230804000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	237007000	USD
	slg	Other Obligations Related To Loan Participations OtherObligationsRelatedToLoanParticipations	0	USD
	slg	Other Obligations Related To Loan Participations OtherObligationsRelatedToLoanParticipations	-16000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3126000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	3842000	USD
	slg	Deferred Loan Costs And Capitalized Lease Obligation DeferredLoanCostsAndCapitalizedLeaseObligation	21068000	USD
	slg	Deferred Loan Costs And Capitalized Lease Obligation DeferredLoanCostsAndCapitalizedLeaseObligation	8257000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-121102000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-809211000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-62569000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	8566000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	216544000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	258592000	USD
	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	471000	USD
	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	1560000	USD
	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	1000000	USD
	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	0	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	10040000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	16246000	USD
	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	15509000	USD
	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	7448000	USD
	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	395000	USD
	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	298391000	USD
	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	403488000	USD
	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	734008000	USD
	slg	Transfer To Liabilities Related To Net Assets Held For Sale TransferToLiabilitiesRelatedToNetAssetsHeldForSale	0	USD
	slg	Transfer To Liabilities Related To Net Assets Held For Sale TransferToLiabilitiesRelatedToNetAssetsHeldForSale	310496000	USD
	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	6602000	USD
	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	115320000	USD
	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	48223000	USD
	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	0	USD
	slg	Share Repurchases Payable ShareRepurchasesPayable	8839000	USD
	slg	Share Repurchases Payable ShareRepurchasesPayable	41746000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	389120000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	121751000	USD
CY2018Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	160248000	USD
CY2019Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	94793000	USD
CY2018Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	98344000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	216544000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	258592000	USD
CY2019Q3	slg	Numberof Real Estate Buildings NumberofRealEstateBuildings	77	building
CY2019Q3	us-gaap	Area Of Real Estate Property AreaOfRealEstateProperty	29540006	sqft
CY2019Q3	slg	Real Estate Weighted Average Occupancy RealEstateWeightedAverageOccupancy	0.935
CY2019Q3	slg	Mortgage Loanson Real Estate Commercialand Consumer Net Including Debt Investments Other MortgageLoansonRealEstateCommercialandConsumerNetIncludingDebtInvestmentsOther	2000000000.0	USD
CY2019Q3	slg	Debt Investments Other DebtInvestmentsOther	100000000	USD
	slg	Number Of Shares On Redemption Of One Unit Of Partnership Interest NumberOfSharesOnRedemptionOfOneUnitOfPartnershipInterest	1	shares
CY2019Q3	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	1200000	USD
	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	3600000	USD
CY2018Q3	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	1300000	USD
	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	5500000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	278192000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	266540000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	248111000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	241040000	USD
CY2019Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	30081000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	25500000	USD
CY2019Q3	slg	Finite Lived Intangible Liabilities Gross FiniteLivedIntangibleLiabilitiesGross	304998000	USD
CY2018Q4	slg	Finite Lived Intangible Liabilities Gross FiniteLivedIntangibleLiabilitiesGross	276245000	USD
CY2019Q3	slg	Finite Lived Intangible Liabilities Accumulated Amortization FiniteLivedIntangibleLiabilitiesAccumulatedAmortization	267429000	USD
CY2018Q4	slg	Finite Lived Intangible Liabilities Accumulated Amortization FiniteLivedIntangibleLiabilitiesAccumulatedAmortization	253767000	USD
CY2019Q3	slg	Finite Lived Intangible Liabilities Net FiniteLivedIntangibleLiabilitiesNet	37569000	USD
CY2018Q4	slg	Finite Lived Intangible Liabilities Net FiniteLivedIntangibleLiabilitiesNet	22478000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1000000.0	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	500000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2000000.0	USD
	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>
	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.
	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
	us-gaap	Mortgage Loans On Real Estate Amortization Of Premium MortgageLoansOnRealEstateAmortizationOfPremium	733592000	USD
CY2018	us-gaap	Mortgage Loans On Real Estate Amortization Of Premium MortgageLoansOnRealEstateAmortizationOfPremium	994906000	USD
	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
CY2019Q3	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	1954556000	USD
CY2018Q4	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	2099393000	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
	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
	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
	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
CY2019Q3	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
CY2019Q3	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	1800000	USD
CY2019Q3	slg	Financing Receivable Number Ofinvestments Marketed For Sale FinancingReceivableNumberOfinvestmentsMarketedForSale	1	loan
CY2019Q3	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	145400000	USD
	slg	Financing Receivable Portfolio Segments Number FinancingReceivablePortfolioSegmentsNumber	1	segment
CY2019Q3	slg	Financing Receivable Recorded In Other Assets FinancingReceivableRecordedInOtherAssets	89800000	USD
CY2018Q4	slg	Financing Receivable Recorded In Other Assets FinancingReceivableRecordedInOtherAssets	88800000	USD
CY2019Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	28400000	USD
CY2018Q4	slg	Debt And Equity Securities Weighted Average Risk Rating DebtAndEquitySecuritiesWeightedAverageRiskRating	1.2
	srt	Mortgage Loans On Real Estate Interest Rate MortgageLoansOnRealEstateInterestRate	0.0889
CY2019Q3	slg	Variable Interest Entity Not Primary Beneficiary Investment VariableInterestEntityNotPrimaryBeneficiaryInvestment	876900000	USD
CY2018Q4	slg	Variable Interest Entity Not Primary Beneficiary Investment VariableInterestEntityNotPrimaryBeneficiaryInvestment	808300000	USD
CY2019Q3	us-gaap	Deferred Costs Leasing Gross DeferredCostsLeasingGross	445489000	USD
CY2018Q4	us-gaap	Deferred Costs Leasing Gross DeferredCostsLeasingGross	453833000	USD
CY2019Q3	slg	Accumulated Amortization Of Deferred Costs AccumulatedAmortizationOfDeferredCosts	262868000	USD
CY2018Q4	slg	Accumulated Amortization Of Deferred Costs AccumulatedAmortizationOfDeferredCosts	244723000	USD
CY2019Q3	us-gaap	Deferred Costs Current And Noncurrent DeferredCostsCurrentAndNoncurrent	182621000	USD
CY2018Q4	us-gaap	Deferred Costs Current And Noncurrent DeferredCostsCurrentAndNoncurrent	209110000	USD
CY2019Q3	slg	Secured Debt Bearing Fixed Interest Amount SecuredDebtBearingFixedInterestAmount	1385756000	USD
CY2018Q4	slg	Secured Debt Bearing Fixed Interest Amount SecuredDebtBearingFixedInterestAmount	1389717000	USD
CY2019Q3	slg	Secured Debt Bearing Variable Interest Amount SecuredDebtBearingVariableInterestAmount	1068927000	USD
CY2018Q4	slg	Secured Debt Bearing Variable Interest Amount SecuredDebtBearingVariableInterestAmount	598442000	USD
CY2019Q3	slg	Secured Debt Gross SecuredDebtGross	2454683000	USD
CY2018Q4	slg	Secured Debt Gross SecuredDebtGross	1988159000	USD
CY2019Q3	slg	Secured Debt Deferred Finance Costs Net SecuredDebtDeferredFinanceCostsNet	37522000	USD
CY2018Q4	slg	Secured Debt Deferred Finance Costs Net SecuredDebtDeferredFinanceCostsNet	26919000	USD
CY2019Q3	us-gaap	Secured Debt SecuredDebt	2417161000	USD
CY2018Q4	us-gaap	Secured Debt SecuredDebt	1961240000	USD
CY2019Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	3700000000	USD
CY2018Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	2600000000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	16807000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	491748000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	596539000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	1546882000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	1692301000	USD
CY2019Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1545406000	USD
CY2019Q3	slg	Long Term Debt Maturities Repayments Of Principal LongTermDebtMaturitiesRepaymentsOfPrincipal	5889683000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	63607000	USD
CY2018Q3	us-gaap	Interest Expense InterestExpense	64078000	USD
	us-gaap	Interest Expense InterestExpense	185163000	USD
	us-gaap	Interest Expense InterestExpense	180550000	USD
CY2019Q3	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	813000	USD
CY2018Q3	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	2425000	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0	USD
CY2019Q3	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	15700000	USD
CY2018Q3	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	8504000	USD
	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	38228000	USD
	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	22785000	USD
CY2019Q3	us-gaap	Interest Income Operating InterestIncomeOperating	608000	USD
CY2018Q3	us-gaap	Interest Income Operating InterestIncomeOperating	406000	USD
	us-gaap	Interest Income Operating InterestIncomeOperating	3563000	USD
	us-gaap	Interest Income Operating InterestIncomeOperating	1070000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-48112000	USD
CY2018Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-55168000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-145797000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-156695000	USD
CY2019Q3	us-gaap	Due From Joint Ventures DueFromJointVentures	7648000	USD
CY2018Q4	us-gaap	Due From Joint Ventures DueFromJointVentures	18655000	USD
CY2019Q3	us-gaap	Due From Other Related Parties DueFromOtherRelatedParties	12382000	USD
CY2018Q4	us-gaap	Due From Other Related Parties DueFromOtherRelatedParties	9378000	USD
CY2019Q3	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	108300	shares
CY2019Q3	us-gaap	Due From Related Parties DueFromRelatedParties	20030000	USD
CY2018Q4	us-gaap	Due From Related Parties DueFromRelatedParties	28033000	USD
	slg	Preferred Stock Convertible Conversion Ratio PreferredStockConvertibleConversionRatio	6.71348
CY2019Q3	slg	Total Shares Authorized TotalSharesAuthorized	260000000	shares
CY2019Q3	slg	Total Par Or Stated Value Per Share TotalParOrStatedValuePerShare	0.01
CY2019Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	160000000	shares
CY2019Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q3	us-gaap	Excess Stock Shares Authorized ExcessStockSharesAuthorized	75000000	shares
CY2019Q3	slg	Excess Stock Par Or Stated Value Per Share ExcessStockParOrStatedValuePerShare	0.01
CY2019Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	25000000	shares
CY2019Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2019Q3	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
CY2019Q1	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	397783	shares
CY2019Q1	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	86.07
CY2019Q2	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	866924	shares
CY2019Q2	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	86.58
CY2019Q3	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	916439	shares
CY2019Q3	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	81.31
CY2019Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	108000	USD
CY2018Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	125000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	325000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	371000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	33157000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	88209000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	238052000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	293531000	USD
CY2019Q3	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	33049000	USD
CY2018Q3	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	88051000	USD
	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	237686000	USD
	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	293022000	USD
CY2019Q3	slg	Distributed Earnings Diluted DistributedEarningsDiluted	0	USD
CY2018Q3	slg	Distributed Earnings Diluted DistributedEarningsDiluted	33000	USD
	slg	Distributed Earnings Diluted DistributedEarningsDiluted	41000	USD
	slg	Distributed Earnings Diluted DistributedEarningsDiluted	138000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	34876000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	93006000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	250358000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	309187000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	82292000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	85566000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	82855000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	87692000	shares
CY2019Q3	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4258000	shares
CY2018Q3	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4643000	shares
	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4283000	shares
	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4677000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	164000	shares
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	219000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	171000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	211000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	86714000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	90428000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	87309000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	92580000	shares
CY2019Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1317803	shares
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	941636	shares
CY2019Q3	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	500000	USD
	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	1400000	USD
CY2018Q3	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	1600000	USD
	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	4700000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-53571000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1669000	USD
CY2019Q3	slg	Other Comprehensive Income Loss Deferred Net Lossfrom Terminated Hedges OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges	-200000	USD
CY2018Q4	slg	Other Comprehensive Income Loss Deferred Net Lossfrom Terminated Hedges OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges	1300000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	30208000	USD
CY2019Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	2784000	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
CY2019Q3	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-100000	USD
	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-100000	USD
CY2019Q3	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-100000	USD
	slg	Accumulated Other Comprehensive Income Loss Gain Lossfrom Changesin Fair Value AccumulatedOtherComprehensiveIncomeLossGainLossfromChangesinFairValue	-400000	USD
CY2019Q3	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	37400000	USD
CY2019Q3	us-gaap	Assets Needed For Immediate Settlement Aggregate Fair Value AssetsNeededForImmediateSettlementAggregateFairValue	38300000	USD
	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	-5500000	USD
	slg	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months Into Equity In Net Income CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsIntoEquityInNetIncome	-3100000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-12606000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	4470000	USD
CY2019Q3	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	297000	USD
CY2018Q3	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-498000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-54971000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	19273000	USD
	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-1599000	USD
	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-530000	USD
CY2019Q3	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	214282000	USD
CY2018Q3	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	220443000	USD
	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	641007000	USD
	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	643015000	USD
CY2019Q3	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	32581000	USD
CY2018Q3	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	29103000	USD
	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	88539000	USD
	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	82554000	USD
CY2019Q3	slg	Operating Lease Lease Income Fixed And Variable Lease Payments OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments	246863000	USD
CY2018Q3	slg	Operating Lease Lease Income Fixed And Variable Lease Payments OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments	249546000	USD
	slg	Operating Lease Lease Income Fixed And Variable Lease Payments OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments	729546000	USD
	slg	Operating Lease Lease Income Fixed And Variable Lease Payments OperatingLeaseLeaseIncomeFixedAndVariableLeasePayments	725569000	USD
CY2019Q3	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	1165000	USD
CY2018Q3	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	1320000	USD
	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	3559000	USD
	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	5486000	USD
CY2019Q3	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	248028000	USD
CY2018Q3	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	250866000	USD
	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	733105000	USD
	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	731055000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Remainder Of Fiscal Year FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear	621000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	7797000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	2619000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	31508000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	2794000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	31702000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	2794000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	29548000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2794000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	27243000	USD
CY2019Q3	slg	Finance Lease Liability Payments Due Year Six FinanceLeaseLiabilityPaymentsDueYearSix	2819000	USD
CY2019Q3	slg	Lessee Operating Lease Liability Payments Due Year Six LesseeOperatingLeaseLiabilityPaymentsDueYearSix	27263000	USD
CY2019Q3	slg	Finance Lease Liability Payments Due After Year Six FinanceLeaseLiabilityPaymentsDueAfterYearSix	814283000	USD
CY2019Q3	slg	Lessee Operating Lease Liability Payments Due After Year Six LesseeOperatingLeaseLiabilityPaymentsDueAfterYearSix	649289000	USD
CY2019Q3	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	828724000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	804350000	USD
CY2019Q3	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	784473000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	419689000	USD
CY2019Q3	us-gaap	Finance Lease Liability FinanceLeaseLiability	44251000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	384661000	USD
CY2019Q3	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	1700000000	USD
	slg	Finance Lease Cost FinanceLeaseCost	3300000	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	2400000	USD
	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	900000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	24900000	USD
CY2019Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0847
CY2019Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P67Y
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2019Q3	us-gaap	Revenues Revenues	313634000	USD
CY2018Q3	us-gaap	Revenues Revenues	307545000	USD
	us-gaap	Revenues Revenues	930913000	USD
	us-gaap	Revenues Revenues	910356000	USD
CY2019Q3	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	40722000	USD
CY2018Q3	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	99454000	USD
	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	267232000	USD
	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	329176000	USD
CY2019Q3	us-gaap	Assets Assets	13294984000	USD
CY2018Q4	us-gaap	Assets Assets	12751358000	USD
CY2019Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	23800000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	75300000	USD
CY2018Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	20600000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	66600000	USD

Files In Submission

Name	View Source	Status
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0001040971-19-000031-index.html	Edgar Link	pending
0001040971-19-000031.txt	Edgar Link	pending
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$SLG
SL GREEN REALTY CORP Stock $slg

2019 Q4 Form 10-Q Financial Statement

#000104097119000031 Filed on November 06, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SLG SL GREEN REALTY CORP Stock $slg

2019 Q4 Form 10-Q Financial Statement

#000104097119000031 Filed on November 06, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SLG
SL GREEN REALTY CORP Stock $slg