$SLG
SL GREEN REALTY CORP Stock $slg

$slg Overview Financials Valuation SEC Filings Company Website

2019 Q2 Form 10-Q Financial Statement

#000104097119000021 Filed on August 08, 2019

Income Statement

Concept	2019 Q2	2018 Q2	2018 Q1
Revenue	$313.0M	$301.1M	$301.7M
YoY Change	3.95%	-24.37%	-20.06%
Cost Of Revenue	$113.3M	$110.4M	$113.8M
YoY Change	2.63%	-21.2%	-20.92%
Gross Profit	$199.7M	$190.7M	$187.9M
YoY Change	4.72%	-26.09%	-19.53%
Gross Profit Margin	63.8%	63.33%	62.28%
Selling, General & Admin	$25.50M	$22.50M	$23.53M
YoY Change	13.33%	-7.24%	-2.55%
% of Gross Profit	12.77%	11.8%	12.52%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$72.20M	$71.50M	$72.93M
YoY Change	0.98%	-47.62%	-26.26%
% of Gross Profit	36.15%	37.49%	38.81%
Operating Expenses	$25.50M	$22.50M	$23.53M
YoY Change	13.33%	-7.24%	-2.55%
Operating Profit	$174.2M	$168.2M	$164.4M
YoY Change	3.57%	-28.04%	-21.49%
Interest Expense	$60.75M	$61.55M	$54.13M
YoY Change	-1.31%	-14.5%	-25.25%
% of Operating Profit	34.87%	36.6%	32.93%
Other Income/Expense, Net		$0.00	$0.00
YoY Change		-100.0%	-100.0%
Pretax Income	$173.7M	$42.81M	$43.41M
YoY Change	305.72%	32.13%	-2.89%
Income Tax	$700.0K	$1.100M	$500.0K
% Of Pretax Income	0.4%	2.57%	1.15%
Net Earnings	$164.8M	$107.3M	$105.5M
YoY Change	53.64%	797.17%	599.21%
Net Earnings / Revenue	52.66%	35.63%	34.97%
Basic Earnings Per Share	$1.94	$1.19	$1.12
Diluted Earnings Per Share	$1.94	$1.19	$1.12
COMMON SHARES
Basic Shares Outstanding	82.97M shares	87.18M shares	90.52M shares
Diluted Shares Outstanding	87.40M shares	92.08M shares	95.26M shares

Balance Sheet

Concept	2019 Q2	2018 Q2	2018 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments	$179.0M	$315.8M	$317.1M
YoY Change	-43.33%	5.1%	-36.24%
Cash & Equivalents	$149.0M	$287.2M	$288.8M
Short-Term Investments	$29.98M	$28.57M	$28.25M
Other Short-Term Assets
YoY Change
Inventory		$594.0M	$68.00M
Prepaid Expenses
Receivables	$404.0M	$398.0M	$401.0M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$553.0M	$1.279B	$758.0M
YoY Change	-56.76%	50.47%	-27.67%
LONG-TERM ASSETS
Property, Plant & Equipment	$7.333B	$6.595B	$6.829B
YoY Change	11.19%	-30.62%	-34.25%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$2.937B	$3.060B	$3.035B
YoY Change	-4.01%	37.88%	63.06%
Other Assets	$313.0M	$292.0M	$285.0M
YoY Change	7.19%	-18.89%	-15.93%
Total Long-Term Assets	$13.08B	$12.43B	$12.62B
YoY Change	5.16%	-14.0%	-14.88%
TOTAL ASSETS
Total Short-Term Assets	$553.0M	$1.279B	$758.0M
Total Long-Term Assets	$13.08B	$12.43B	$12.62B
Total Assets	$13.63B	$13.71B	$13.38B
YoY Change	-0.61%	-10.42%	-15.72%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$133.0M	$141.0M	$132.0M
YoY Change	-5.67%	5.22%	-21.89%
Accrued Expenses	$413.0M	$26.00M	$37.00M
YoY Change	1488.46%	-27.78%	8.82%
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	$688.0M	$314.0M	$319.0M
YoY Change	119.11%	-3.98%	-11.39%
LONG-TERM LIABILITIES
Long-Term Debt	$6.127B	$5.901B	$5.465B
YoY Change	3.83%	-8.07%	-17.47%
Other Long-Term Liabilities	$247.0M	$469.0M	$282.0M
YoY Change	-47.33%	10.09%	-29.15%
Total Long-Term Liabilities	$6.374B	$6.370B	$5.747B
YoY Change	0.06%	-6.94%	-18.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$688.0M	$314.0M	$319.0M
Total Long-Term Liabilities	$6.374B	$6.370B	$5.747B
Total Liabilities	$7.062B	$6.684B	$6.066B
YoY Change	5.66%	-6.81%	-17.81%
SHAREHOLDERS EQUITY
Retained Earnings	$1.288B	$1.458B	$1.584B
YoY Change	-11.62%	1.84%	5.82%
Common Stock	$835.0K	$868.0K	$902.0K
YoY Change	-3.8%	-12.76%	-11.48%
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	1.055M shares	1.055M shares	1.055M shares
Shareholders Equity	$5.810B	$6.191B	$6.488B
YoY Change
Total Liabilities & Shareholders Equity	$13.63B	$13.71B	$13.38B
YoY Change	-0.61%	-10.42%	-15.72%

Cashflow Statement

Concept	2019 Q2	2018 Q2	2018 Q1
OPERATING ACTIVITIES
Net Income	$164.8M	$107.3M	$105.5M
YoY Change	53.64%	797.17%	599.21%
Depreciation, Depletion And Amortization	$72.20M	$71.50M	$72.93M
YoY Change	0.98%	-47.62%	-26.26%
Cash From Operating Activities	$155.6M	$151.7M	$94.55M
YoY Change	2.57%	-23.31%	-16.44%
INVESTING ACTIVITIES
Capital Expenditures	-$315.9M	-$53.40M	-$52.90M
YoY Change	491.57%	-16.82%	-47.68%
Acquisitions
YoY Change
Other Investing Activities	$141.3M	-$134.5M	$508.9M
YoY Change	-205.06%	-29.47%	329.81%
Cash From Investing Activities	-$174.6M	-$187.9M	$456.0M
YoY Change	-7.08%	-26.28%	2532.65%
FINANCING ACTIVITIES
Cash Dividend Paid			$81.73M
YoY Change			-2.91%
Common Stock Issuance & Retirement, Net			$382.7M
YoY Change			375075.49%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-35.60M	38.00M	-$422.3M
YoY Change	-193.68%	-137.59%	-1188.06%
NET CHANGE
Cash From Operating Activities	155.6M	151.7M	$94.55M
Cash From Investing Activities	-174.6M	-187.9M	$456.0M
Cash From Financing Activities	-35.60M	38.00M	-$422.3M
Net Change In Cash	-54.60M	1.800M	$128.2M
YoY Change	-3133.33%	-101.14%	-24.25%
FREE CASH FLOW
Cash From Operating Activities	$155.6M	$151.7M	$94.55M
Capital Expenditures	-$315.9M	-$53.40M	-$52.90M
Free Cash Flow	$471.5M	$205.1M	$147.4M
YoY Change	129.89%	-21.72%	-31.18%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
	dei	Entity Central Index Key EntityCentralIndexKey	0001040971
	dei	Entity Small Business EntitySmallBusiness	false
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CY2019Q2	slg	Discount Of Structured Finance Investments DiscountOfStructuredFinanceInvestments	19963000	USD
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	us-gaap	Affiliate Costs AffiliateCosts	8499000	USD
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	us-gaap	Affiliate Costs AffiliateCosts	8116000	USD
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	dei	Local Phone Number LocalPhoneNumber	594-2700
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Small Business EntitySmallBusiness	false
	dei	City Area Code CityAreaCode	212
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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-06-30
	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	13-3956755
	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	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2018Q2	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	22479000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	51459000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	46007000	USD
CY2019Q2	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	258383000	USD
CY2018Q2	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	258303000	USD
	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	518711000	USD
	slg	Total Costs And Expenses Including Nonoperating Income Expense TotalCostsAndExpensesIncludingNonoperatingIncomeExpense	516585000	USD
CY2019Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-7546000	USD
CY2019Q2	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	8310000	USD
	us-gaap	Profit Loss ProfitLoss	229722000	USD
CY2018Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	4702000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-12780000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	8738000	USD
CY2019Q2	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	59015000	USD
CY2018Q2	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	72025000	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	65585000	USD
CY2019Q2	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	67631000	USD
CY2018Q2	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	11149000	USD
	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	65590000	USD
	slg	Purchase Price Fair Value Adjustment Gross PurchasePriceFairValueAdjustmentGross	60442000	USD
CY2019Q2	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	0	USD
CY2018Q2	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	-14790000	USD
	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	-1049000	USD
	us-gaap	Gain Loss On Sale Of Properties Net Of Applicable Income Taxes GainLossOnSaleOfPropertiesNetOfApplicableIncomeTaxes	8731000	USD
CY2019Q2	us-gaap	Profit Loss ProfitLoss	173741000	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	115899000	USD
	us-gaap	Profit Loss ProfitLoss	226510000	USD
CY2018Q2	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	5586000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	10587000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Operating Partnerships Redeemable NoncontrollingInterestInNetIncomeLossOperatingPartnershipsRedeemable	10858000	USD
CY2019Q2	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-2138000	USD
CY2018Q2	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	173000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	-1900000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Other Noncontrolling Interests Redeemable NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsRedeemable	371000	USD
CY2019Q2	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	2729000	USD
CY2018Q2	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	2847000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	5453000	USD
	us-gaap	Noncontrolling Interest In Net Income Loss Preferred Unit Holders Redeemable NoncontrollingInterestInNetIncomeLossPreferredUnitHoldersRedeemable	5696000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	164840000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	107293000	USD
	us-gaap	Net Income Loss NetIncomeLoss	212370000	USD
	us-gaap	Net Income Loss NetIncomeLoss	212797000	USD
CY2019Q2	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2018Q2	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	7475000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	7475000	USD
CY2019Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	161103000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	103556000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	204895000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	205322000	USD
CY2019Q2	us-gaap	Profit Loss ProfitLoss	173741000	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	115899000	USD
	us-gaap	Profit Loss ProfitLoss	226510000	USD
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.94
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.19
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.46
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.31
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.94
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.19
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.46
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.31
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	82971000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	87176000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	83141000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	88772000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	87398000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	92083000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	87606000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	93667000	shares
	us-gaap	Profit Loss ProfitLoss	229722000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-26220000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	3977000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-47105000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	14890000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	572000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	318000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	1341000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-8000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-25648000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4295000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-45764000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	14882000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	148093000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	120194000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	180746000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	244604000	USD
CY2019Q2	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	8901000	USD
CY2018Q2	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	8606000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	14140000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	16925000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-1258000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	245000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-2261000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	864000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	140450000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	111343000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	168867000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	226815000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5947855000	USD
CY2019Q1	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	47767000	USD
CY2019Q1	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	0	USD
CY2019Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-19113000	USD
CY2019Q1	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2019Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	47000	USD
CY2019Q1	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	446000	USD
CY2019Q1	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	-28932000	USD
CY2019Q1	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-4835000	USD
CY2019Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	34243000	USD
CY2019Q1	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	161000	USD
CY2019Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	208000	USD
CY2019Q1	us-gaap	Dividends Common Stock DividendsCommonStock	70554000	USD
CY2019Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5844323000	USD
CY2019Q2	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	162702000	USD
CY2019Q2	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	25791000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-24390000	USD
CY2019Q2	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	216000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	0	USD
CY2019Q2	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	14904000	USD
CY2019Q2	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-5698000	USD
CY2019Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	75070000	USD
CY2019Q2	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	50532000	USD
CY2019Q2	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	0	USD
CY2019Q2	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	63000	USD
CY2019Q2	us-gaap	Dividends Common Stock DividendsCommonStock	69823000	USD
CY2019Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5879501000	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
CY2018Q1	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	105702000	USD
CY2018Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	9969000	USD
CY2018Q1	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3738000	USD
CY2018Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	42000	USD
	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	0	USD
CY2018Q1	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	3645000	USD
CY2018Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	22000	USD
CY2018Q1	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-3102000	USD
CY2018Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	354744000	USD
CY2018Q1	slg	Common Stock Issued During Period Value New Issues CommonStockIssuedDuringPeriodValueNewIssues	729000	USD
CY2018Q1	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	157000	USD
CY2018Q1	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	314596000	USD
CY2018Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	276000	USD
CY2018Q1	us-gaap	Dividends Common Stock DividendsCommonStock	72341000	USD
CY2018Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6537629000	USD
CY2018Q2	slg	Profit Loss Less Minority Interest In Net Income Loss Operating Partnerships ProfitLossLessMinorityInterestInNetIncomeLossOperatingPartnerships	107466000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4049000	USD
CY2018Q2	us-gaap	Dividends Preferred Stock DividendsPreferredStock	3737000	USD
CY2018Q2	us-gaap	Stock Issued During Period Value Conversion Of Units StockIssuedDuringPeriodValueConversionOfUnits	1560000	USD
CY2018Q2	slg	Reallocationof Noncontrolling Interesttofrom Operating Partnership ReallocationofNoncontrollingInteresttofromOperatingPartnership	-8138000	USD
CY2018Q2	slg	Deferred Compensation Plan And Stock Award Net DeferredCompensationPlanAndStockAwardNet	-4988000	USD
CY2018Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	338347000	USD
CY2018Q2	slg	Common Stock Issued During Period Value New Issues CommonStockIssuedDuringPeriodValueNewIssues	4908000	USD
CY2018Q2	slg	Consolidation Of Joint Venture Interest ConsolidationOfJointVentureInterest	1671000	USD
CY2018Q2	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	0	USD
CY2018Q2	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	448000	USD
CY2018Q2	us-gaap	Dividends Common Stock DividendsCommonStock	69567000	USD
CY2018Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6242056000	USD
	us-gaap	Profit Loss ProfitLoss	226510000	USD
	us-gaap	Profit Loss ProfitLoss	229722000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	143258000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	144385000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-12780000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	8738000	USD
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	566000	USD
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	9889000	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	65585000	USD
	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	65590000	USD
	slg	Purchase Price Fair Value Adjustment Gain Loss PurchasePriceFairValueAdjustmentGainLoss	60442000	USD
	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	-1049000	USD
	us-gaap	Gains Losses On Sales Of Investment Real Estate GainsLossesOnSalesOfInvestmentRealEstate	8731000	USD
	us-gaap	Straight Line Rent StraightLineRent	5674000	USD
	us-gaap	Straight Line Rent StraightLineRent	4369000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-5431000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-9404000	USD
	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	1109000	USD
	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	397000	USD
	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	-427000	USD
	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	-4481000	USD
	us-gaap	Increase Decrease In Due From Related Parties Current IncreaseDecreaseInDueFromRelatedPartiesCurrent	1116000	USD
	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	32183000	USD
	us-gaap	Increase Decrease In Deferred Leasing Fees IncreaseDecreaseInDeferredLeasingFees	17469000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	295000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	4329000	USD
	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	5299000	USD
	slg	Increase Decrease In Accrued Liabilities And Other IncreaseDecreaseInAccruedLiabilitiesAndOther	22867000	USD
	us-gaap	Increase Decrease In Deferred Liabilities IncreaseDecreaseInDeferredLiabilities	1121000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	217915000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	246212000	USD
	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	262343000	USD
	us-gaap	Payments To Acquire Real Estate PaymentsToAcquireRealEstate	9733000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	93013000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	96577000	USD
	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	228000	USD
	slg	Payments For Acquisition Deposits And Deferred Purchase Price PaymentsForAcquisitionDepositsAndDeferredPurchasePrice	1520000	USD
	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	97447000	USD
	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	254305000	USD
	slg	Proceeds From Equity Method Investment Dividends Or Distributions ProceedsFromEquityMethodInvestmentDividendsOrDistributions	45241000	USD
	slg	Proceeds From Equity Method Investment Dividends Or Distributions ProceedsFromEquityMethodInvestmentDividendsOrDistributions	178892000	USD
	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	138526000	USD
	us-gaap	Proceeds From Real Estate And Real Estate Joint Ventures ProceedsFromRealEstateAndRealEstateJointVentures	760335000	USD
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	1056000	USD
	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	22790000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	523476000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	603575000	USD
	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	327392000	USD
	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	317337000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-466404000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	268064000	USD
	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	427352000	USD
	us-gaap	Proceeds From Issuance Of Secured Debt ProceedsFromIssuanceOfSecuredDebt	210575000	USD
	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	43630000	USD
	us-gaap	Repayments Of Secured Debt RepaymentsOfSecuredDebt	22864000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	940000000	USD
	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	1475000000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	770000000	USD
	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1155000000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	263000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	5701000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	109313000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	724696000	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	15851000	USD
	slg	Payments For Repurchase Of Partnership Units PaymentsForRepurchaseOfPartnershipUnits	0	USD
	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	271000	USD
	slg	Distributions To Noncontrolling Interests Other Partnerships DistributionsToNoncontrollingInterestsOtherPartnerships	724000	USD
	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	2469000	USD
	slg	Proceeds From Noncontrolling Interests In Other Partnerships ProceedsFromNoncontrollingInterestsInOtherPartnerships	1828000	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	7353000	USD
	slg	Distribution To Noncontrolling Interest Operating Partnership DistributionToNoncontrollingInterestOperatingPartnership	7712000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	154460000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	160699000	USD
	slg	Other Obligations Related To Loan Participations OtherObligationsRelatedToLoanParticipations	0	USD
	slg	Other Obligations Related To Loan Participations OtherObligationsRelatedToLoanParticipations	3000	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	14624000	USD
	slg	Deferred Loan Costs And Capitalized Lease Obligation DeferredLoanCostsAndCapitalizedLeaseObligation	1536000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	210523000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-384322000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-37966000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	129954000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	241147000	USD
CY2018Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	379980000	USD
	us-gaap	Partners Capital Account Sale Of Units PartnersCapitalAccountSaleOfUnits	0	USD
	us-gaap	Partners Capital Account Sale Of Units PartnersCapitalAccountSaleOfUnits	15448000	USD
	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	446000	USD
	us-gaap	Partners Capital Account Redemptions PartnersCapitalAccountRedemptions	1560000	USD
	slg	Derivative Instruments Fair Value Adjustment DerivativeInstrumentsFairValueAdjustment	0	USD
	slg	Derivative Instruments Fair Value Adjustment DerivativeInstrumentsFairValueAdjustment	6937000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	9021000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	16534000	USD
	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	43835000	USD
	slg	Operating Partnership Noncontrolling Interest Fair Value Adjustment OperatingPartnershipNoncontrollingInterestFairValueAdjustment	4493000	USD
	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	0	USD
	slg	Deconsolidation Real Estate Investments DeconsolidationRealEstateInvestments	298403000	USD
	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	0	USD
	slg	Transfer To Net Assets Held For Sale TransferToNetAssetsHeldForSale	593995000	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	265538000	USD
	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	5728000	USD
	slg	Removalof Fully Depreciated Real Estate Assets RemovalofFullyDepreciatedRealEstateAssets	110594000	USD
	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	48223000	USD
CY2018Q2	slg	Increase Decreasein Noncontrolling Interestin Joint Ventures IncreaseDecreaseinNoncontrollingInterestinJointVentures	0	USD
	slg	Share Repurchases Payable ShareRepurchasesPayable	0	USD
	slg	Share Repurchases Payable ShareRepurchasesPayable	31605000	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
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	148978000	USD
CY2018Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	287240000	USD
CY2019Q2	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	92169000	USD
CY2018Q2	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	92740000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	241147000	USD
CY2018Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	379980000	USD
CY2019Q2	slg	Numberof Real Estate Buildings NumberofRealEstateBuildings	77	building
CY2019Q2	us-gaap	Area Of Real Estate Property AreaOfRealEstateProperty	29540006	sqft
CY2019Q2	slg	Real Estate Weighted Average Occupancy RealEstateWeightedAverageOccupancy	0.932
CY2019Q2	slg	Mortgage Loanson Real Estate Commercialand Consumer Net Including Debt Investments Other MortgageLoansonRealEstateCommercialandConsumerNetIncludingDebtInvestmentsOther	2300000000	USD
CY2019Q2	slg	Debt Investments Other DebtInvestmentsOther	100000000	USD
	slg	Number Of Shares On Redemption Of One Unit Of Partnership Interest NumberOfSharesOnRedemptionOfOneUnitOfPartnershipInterest	1	shares
CY2019Q2	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	1200000	USD
	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	2400000	USD
CY2018Q2	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	1800000	USD
	slg	Rental Revenue Increase Decrease Acquired Lease Amortization RentalRevenueIncreaseDecreaseAcquiredLeaseAmortization	4200000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	282932000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	266540000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	247418000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	241040000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	35514000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	25500000	USD
CY2019Q2	slg	Finite Lived Intangible Liabilities Gross FiniteLivedIntangibleLiabilitiesGross	311091000	USD
CY2018Q4	slg	Finite Lived Intangible Liabilities Gross FiniteLivedIntangibleLiabilitiesGross	276245000	USD
CY2019Q2	slg	Finite Lived Intangible Liabilities Accumulated Amortization FiniteLivedIntangibleLiabilitiesAccumulatedAmortization	258222000	USD
CY2018Q4	slg	Finite Lived Intangible Liabilities Accumulated Amortization FiniteLivedIntangibleLiabilitiesAccumulatedAmortization	253767000	USD
CY2019Q2	slg	Finite Lived Intangible Liabilities Net FiniteLivedIntangibleLiabilitiesNet	52869000	USD
CY2018Q4	slg	Finite Lived Intangible Liabilities Net FiniteLivedIntangibleLiabilitiesNet	22478000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	700000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1500000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1100000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1600000	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	417401000	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
CY2019Q2	us-gaap	Mortgage Loans On Real Estate MortgageLoansOnRealEstate	2228912000	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
CY2019Q2	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
CY2019Q2	us-gaap	Allowance For Loan And Lease Losses Real Estate AllowanceForLoanAndLeaseLossesRealEstate	1800000	USD
CY2019Q2	slg	Financing Receivable Number Ofinvestments Marketed For Sale FinancingReceivableNumberOfinvestmentsMarketedForSale	1	loan
CY2019Q2	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	145100000	USD
	slg	Financing Receivable Portfolio Segments Number FinancingReceivablePortfolioSegmentsNumber	1	segment
CY2019Q2	slg	Financing Receivable Recorded In Other Assets FinancingReceivableRecordedInOtherAssets	87200000	USD
CY2018Q4	slg	Financing Receivable Recorded In Other Assets FinancingReceivableRecordedInOtherAssets	88800000	USD
CY2019Q2	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	28400000	USD
CY2018Q4	slg	Debt And Equity Securities Weighted Average Risk Rating DebtAndEquitySecuritiesWeightedAverageRiskRating	1.3
	srt	Mortgage Loans On Real Estate Interest Rate MortgageLoansOnRealEstateInterestRate	0.0900
CY2019Q2	slg	Variable Interest Entity Not Primary Beneficiary Investment VariableInterestEntityNotPrimaryBeneficiaryInvestment	873000000.0	USD
CY2018Q4	slg	Variable Interest Entity Not Primary Beneficiary Investment VariableInterestEntityNotPrimaryBeneficiaryInvestment	808300000	USD
CY2019Q2	us-gaap	Deferred Costs Leasing Gross DeferredCostsLeasingGross	481204000	USD
CY2018Q4	us-gaap	Deferred Costs Leasing Gross DeferredCostsLeasingGross	453833000	USD
CY2019Q2	slg	Accumulated Amortization Of Deferred Costs AccumulatedAmortizationOfDeferredCosts	260632000	USD
CY2018Q4	slg	Accumulated Amortization Of Deferred Costs AccumulatedAmortizationOfDeferredCosts	244723000	USD
CY2019Q2	us-gaap	Deferred Costs Current And Noncurrent DeferredCostsCurrentAndNoncurrent	220572000	USD
CY2018Q4	us-gaap	Deferred Costs Current And Noncurrent DeferredCostsCurrentAndNoncurrent	209110000	USD
CY2019Q2	slg	Secured Debt Bearing Fixed Interest Amount SecuredDebtBearingFixedInterestAmount	1387182000	USD
CY2018Q4	slg	Secured Debt Bearing Fixed Interest Amount SecuredDebtBearingFixedInterestAmount	1389717000	USD
CY2019Q2	slg	Secured Debt Bearing Variable Interest Amount SecuredDebtBearingVariableInterestAmount	979725000	USD
CY2018Q4	slg	Secured Debt Bearing Variable Interest Amount SecuredDebtBearingVariableInterestAmount	598442000	USD
CY2019Q2	slg	Secured Debt Gross SecuredDebtGross	2366907000	USD
CY2018Q4	slg	Secured Debt Gross SecuredDebtGross	1988159000	USD
CY2019Q2	slg	Secured Debt Deferred Finance Costs Net SecuredDebtDeferredFinanceCostsNet	36494000	USD
CY2018Q4	slg	Secured Debt Deferred Finance Costs Net SecuredDebtDeferredFinanceCostsNet	26919000	USD
CY2019Q2	us-gaap	Secured Debt SecuredDebt	2330413000	USD
CY2018Q4	us-gaap	Secured Debt SecuredDebt	1961240000	USD
CY2019Q2	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	3500000000	USD
CY2018Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	2600000000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	31233000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	568772000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	590718000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	1307926000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	2092851000	USD
CY2019Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1545407000	USD
CY2019Q2	slg	Long Term Debt Maturities Repayments Of Principal LongTermDebtMaturitiesRepaymentsOfPrincipal	6136907000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	60745000	USD
CY2018Q2	us-gaap	Interest Expense InterestExpense	61553000	USD
	us-gaap	Interest Expense InterestExpense	121555000	USD
	us-gaap	Interest Expense InterestExpense	116471000	USD
CY2019Q2	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	808000	USD
CY2018Q2	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	1612000	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0	USD
CY2019Q2	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	12019000	USD
CY2018Q2	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	7594000	USD
	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	22528000	USD
	us-gaap	Interest Costs Incurred Capitalized InterestCostsIncurredCapitalized	14280000	USD
CY2019Q2	us-gaap	Interest Income Operating InterestIncomeOperating	2374000	USD
CY2018Q2	us-gaap	Interest Income Operating InterestIncomeOperating	348000	USD
	us-gaap	Interest Income Operating InterestIncomeOperating	2954000	USD
	us-gaap	Interest Income Operating InterestIncomeOperating	664000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-47160000	USD
CY2018Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-53611000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-97685000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	-101527000	USD
CY2019Q2	us-gaap	Due From Joint Ventures DueFromJointVentures	8879000	USD
CY2018Q4	us-gaap	Due From Joint Ventures DueFromJointVentures	18655000	USD
CY2019Q2	us-gaap	Due From Other Related Parties DueFromOtherRelatedParties	14807000	USD
CY2019Q2	slg	Total Par Or Stated Value Per Share TotalParOrStatedValuePerShare	0.01
CY2019Q2	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	160000000	shares
CY2019Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2018Q4	us-gaap	Due From Other Related Parties DueFromOtherRelatedParties	9378000	USD
CY2019Q2	us-gaap	Due From Related Parties DueFromRelatedParties	23686000	USD
CY2018Q4	us-gaap	Due From Related Parties DueFromRelatedParties	28033000	USD
	slg	Preferred Stock Convertible Conversion Ratio PreferredStockConvertibleConversionRatio	6.71348
CY2019Q2	slg	Total Shares Authorized TotalSharesAuthorized	260000000	shares
CY2019Q2	us-gaap	Excess Stock Shares Authorized ExcessStockSharesAuthorized	75000000	shares
CY2019Q2	slg	Excess Stock Par Or Stated Value Per Share ExcessStockParOrStatedValuePerShare	0.01
CY2019Q2	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	25000000	shares
CY2019Q2	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2019Q2	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
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	397783	shares
	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
CY2019Q2	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	169413000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	204895000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	205322000	USD
CY2019Q2	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	160811000	USD
CY2018Q2	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	103382000	USD
	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	204523000	USD
	slg	Net Income Loss Available To Common Stockholders After Distributed And Undistributed Earnings Allocation Basic NetIncomeLossAvailableToCommonStockholdersAfterDistributedAndUndistributedEarningsAllocationBasic	204985000	USD
CY2019Q2	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	128000	USD
CY2018Q2	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	119000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	257000	USD
CY2019Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	161103000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	103556000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	237000	USD
CY2019Q2	slg	Distributed Earnings Diluted DistributedEarningsDiluted	164000	USD
CY2018Q2	slg	Distributed Earnings Diluted DistributedEarningsDiluted	55000	USD
	slg	Distributed Earnings Diluted DistributedEarningsDiluted	115000	USD
	slg	Distributed Earnings Diluted DistributedEarningsDiluted	100000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	109142000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	215482000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	216180000	USD
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	82971000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	87176000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	83141000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	88772000	shares
CY2019Q2	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4260000	shares
CY2018Q2	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4706000	shares
	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4296000	shares
	slg	Incremental Common Shares Attributable To Redemption Of Units To Common Shares IncrementalCommonSharesAttributableToRedemptionOfUnitsToCommonShares	4695000	shares
CY2019Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	167000	shares
CY2018Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	201000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	169000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	200000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	87398000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	92083000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	87606000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	93667000	shares
CY2019Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1246040	shares
CY2018Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1158317	shares
CY2019Q2	us-gaap	Available For Sale Securities AvailableForSaleSecurities	29978000	USD
CY2019Q2	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	5683000	USD
CY2019Q2	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	900000	USD
CY2018Q2	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	3200000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-41528000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1975000	USD
CY2019Q2	slg	Other Comprehensive Income Loss Deferred Net Lossfrom Terminated Hedges OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges	300000	USD
CY2018Q4	slg	Other Comprehensive Income Loss Deferred Net Lossfrom Terminated Hedges OtherComprehensiveIncomeLossDeferredNetLossfromTerminatedHedges	1300000	USD
CY2018Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	28638000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	18676000	USD
CY2019Q2	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	-300000	USD
CY2019Q2	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	29600000	USD
CY2019Q2	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
CY2019Q2	us-gaap	Assets Needed For Immediate Settlement Aggregate Fair Value AssetsNeededForImmediateSettlementAggregateFairValue	30500000	USD
	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	-3900000	USD
CY2018Q2	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	27052000	USD
	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	55958000	USD
	slg	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months Into Equity In Net Income CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonthsIntoEquityInNetIncome	-2200000	USD
CY2019Q2	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	-25033000	USD
CY2018Q2	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	4208000	USD
CY2019Q2	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-992000	USD
CY2018Q2	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-264000	USD
	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	-42365000	USD
	us-gaap	Unrealized Gain Loss On Interest Rate Cash Flow Hedges Pretax Accumulated Other Comprehensive Income Loss UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss	14803000	USD
	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-1896000	USD
	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	-32000	USD
CY2019Q2	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	215295000	USD
CY2018Q2	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	209565000	USD
	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	426725000	USD
	us-gaap	Operating Lease Lease Income Lease Payments OperatingLeaseLeaseIncomeLeasePayments	422572000	USD
CY2019Q2	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	28479000	USD
	us-gaap	Operating Lease Variable Lease Income OperatingLeaseVariableLeaseIncome	53451000	USD
CY2019Q2	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	243774000	USD
CY2018Q2	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	236617000	USD
	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	482683000	USD
	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	476023000	USD
CY2019Q2	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	1185000	USD
CY2018Q2	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	1804000	USD
	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	2394000	USD
	us-gaap	Amortization Of Above And Below Market Leases AmortizationOfAboveAndBelowMarketLeases	4166000	USD
CY2019Q2	us-gaap	Operating Leases Income Statement Minimum Lease Revenue OperatingLeasesIncomeStatementMinimumLeaseRevenue	244959000	USD
CY2018Q2	us-gaap	Operating Leases Income Statement Minimum Lease Revenue OperatingLeasesIncomeStatementMinimumLeaseRevenue	238421000	USD
	us-gaap	Operating Leases Income Statement Minimum Lease Revenue OperatingLeasesIncomeStatementMinimumLeaseRevenue	485077000	USD
	us-gaap	Operating Leases Income Statement Minimum Lease Revenue OperatingLeasesIncomeStatementMinimumLeaseRevenue	480189000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Remainder Of Fiscal Year FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear	1218000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	15576000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	2619000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	31508000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	2794000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	31702000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	2794000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	29548000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2794000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	27243000	USD
CY2019Q2	slg	Finance Lease Liability Payments Due Year Six FinanceLeaseLiabilityPaymentsDueYearSix	2819000	USD
CY2019Q2	slg	Lessee Operating Lease Liability Payments Due Year Six LesseeOperatingLeaseLiabilityPaymentsDueYearSix	27263000	USD
CY2019Q2	slg	Finance Lease Liability Payments Due After Year Six FinanceLeaseLiabilityPaymentsDueAfterYearSix	814283000	USD
CY2019Q2	slg	Lessee Operating Lease Liability Payments Due After Year Six LesseeOperatingLeaseLiabilityPaymentsDueAfterYearSix	649289000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	829321000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	812129000	USD
CY2019Q2	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	785287000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	424527000	USD
CY2019Q2	us-gaap	Finance Lease Liability FinanceLeaseLiability	44034000	USD
CY2019Q2	us-gaap	Operating Lease Liability OperatingLeaseLiability	387602000	USD
CY2019Q2	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	1700000000	USD
	slg	Finance Lease Cost FinanceLeaseCost	2200000	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	1600000	USD
	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	600000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	16600000	USD
CY2019Q2	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0846
CY2019Q2	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P67Y
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2019Q2	us-gaap	Revenues Revenues	313024000	USD
CY2018Q2	us-gaap	Revenues Revenues	301116000	USD
	us-gaap	Revenues Revenues	617279000	USD
	us-gaap	Revenues Revenues	602811000	USD
CY2019Q2	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	173741000	USD
CY2018Q2	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	115899000	USD
	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	226510000	USD
	slg	Income Loss From Continuing Operations Before Realized Gain Loss On Disposal Of Equity Method Investment IncomeLossFromContinuingOperationsBeforeRealizedGainLossOnDisposalOfEquityMethodInvestment	229722000	USD
CY2019Q2	us-gaap	Assets Assets	13629941000	USD
CY2018Q4	us-gaap	Assets Assets	12751358000	USD
CY2019Q2	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	25500000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	51500000	USD
CY2018Q2	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	22500000	USD
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	46000000.0	USD

Files In Submission

Name	View Source	Status
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0001040971-19-000021.txt	Edgar Link	pending
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$SLG
SL GREEN REALTY CORP Stock $slg

2019 Q2 Form 10-Q Financial Statement

#000104097119000021 Filed on August 08, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SLG SL GREEN REALTY CORP Stock $slg

2019 Q2 Form 10-Q Financial Statement

#000104097119000021 Filed on August 08, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SLG
SL GREEN REALTY CORP Stock $slg