Reckson Operating Partnership 10-K 10 Mar 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2016	Mar. 09, 2017	Jun. 30, 2016
Document and Entity Information
Entity Registrant Name	RECKSON OPERATING PARTNERSHIP LP
Entity Central Index Key	930,810
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Public Float			$ 0
Entity Common Stock, Shares Outstanding		0
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Commercial real estate properties, at cost:
Land and land interests	$ 1,805,198	$ 1,877,492
Building and improvements	4,629,994	4,477,073
Building leasehold and improvements	1,073,678	1,073,678
Commercial real estate properties, gross	7,508,870	7,428,243
Less: accumulated depreciation	(1,437,222)	(1,267,598)
Total commercial real estate properties, net	6,071,648	6,160,645
Cash and cash equivalents	59,930	50,026
Restricted cash	43,489	39,433
Tenant and other receivables, net of allowance of $4,879 and $5,593 in 2016 and 2015, respectively	30,999	35,256
Deferred rents receivable, net of allowance of $17,798 and $14,788 in 2016 and 2015, respectively	238,447	217,730
Related party receivable	0	90,000
Debt, preferred equity and other investments, net of discounts and deferred origination fees of $16,705 and $18,759 in 2016 and 2015, respectively	1,640,412	1,670,020
Investments in joint ventures	174,127	100,192
Deferred costs, net of accumulated amortization of $73,673 and $64,812 in 2016 and 2015, respectively	121,470	114,449
Other assets	374,091	355,566
Total assets	8,754,613	8,833,317
Liabilities
Mortgages and other loans payable, net	676,068	745,728
Revolving credit facility, net	0	985,055
Unsecured term loan, net	1,179,521	929,514
Unsecured notes, net	795,260	1,049,803
Accrued interest payable	15,781	18,396
Other liabilities	160,982	116,088
Accounts payable and accrued expenses	60,855	70,844
Related party payables	23,808	0
Deferred revenue	161,772	180,404
Deferred land leases payable	1,795	1,558
Dividends payable	754	807
Security deposits	40,033	39,007
Total liabilities	3,116,629	4,137,204
Commitments and contingencies	0	0
Preferred units	109,161	109,161
Capital
General partner capital	5,139,842	4,201,872
Limited partner capital	0	0
Accumulated other comprehensive loss	(1,618)	(2,216)
Total ROP partner's capital	5,138,224	4,199,656
Noncontrolling interests in other partnerships	390,599	387,296
Total capital	5,528,823	4,586,952
Total liabilities and capital	$ 8,754,613	$ 8,833,317

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Tenant and other receivables, allowance	$ 4,879	$ 5,593
Deferred rents receivable, allowance	17,798	14,788
Preferred equity investments, deferred origination fees and discounts	16,705	18,759
Deferred costs, accumulated amortization	$ 73,673	$ 64,812

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Rental revenue, net	$ 652,629	$ 621,121	$ 574,150
Escalation and reimbursement	104,683	95,894	92,850
Investment income	214,102	182,648	176,901
Other income	4,002	25,570	3,621
Total revenues	975,416	925,233	847,522
Expenses
Operating expenses, including $25,193 in 2016, $26,728 in 2015, and $25,094 in 2014 of related party expenses	166,137	163,969	154,374
Real estate taxes	152,010	143,873	133,567
Ground rent	20,971	20,941	20,941
Interest expense, net of interest income	109,208	119,342	129,356
Amortization of deferred financing costs	7,918	7,519	7,810
Depreciation and amortization	212,514	202,474	196,505
Transaction related costs	238	2,871	3,599
Marketing, general and administrative	720	464	372
Total expenses	669,716	661,453	646,524
Income from continuing operations before equity in net income from unconsolidated joint ventures, equity in net gain on sale of interest in unconsolidated joint venture, (loss) gain on sale of real estate, depreciable real estate reserves and loss on early extinguishment of debt	305,700	263,780	200,998
Equity in net income from unconsolidated joint ventures	14,509	8,841	4,491
Equity in net gain on sale of interest in unconsolidated joint venture	0	0	85,559
(Loss) gain on sale of real estate	(6,909)	100,190	0
Depreciable real estate reserves	0	(9,998)	0
Loss on early extinguishment of debt	0	(49)	(7,385)
Income from continuing operations	313,300	362,764	283,663
Net income from discontinued operations	0	0	1,996
Gain on sale of discontinued operations	0	0	117,579
Net income	313,300	362,764	403,238
Net income attributable to noncontrolling interests in other partnerships	(4,424)	(9,169)	(2,641)
Preferred units dividend	(3,821)	(1,698)	0
Net income attributable to ROP common unitholder	305,055	351,897	400,597
Amounts attributable to ROP common unitholder:
Income from continuing operations	305,055	351,897	281,022
Discontinued operations	$ 0	$ 0	$ 119,575

Consolidated Statements of Ope5

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Related party expenses included in operating expenses	$ 25,193	$ 26,728	$ 25,094

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income attributable to ROP common unitholder	$ 305,055	$ 351,897	$ 400,597
Other comprehensive income:
Change in net unrealized gain on derivative instruments	598	890	835
Comprehensive income attributable to ROP common unitholder	$ 305,653	$ 352,787	$ 401,432

Consolidated Statement of Capit

Consolidated Statement of Capital - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Increase (Decrease) in Partners' Capital
Beginning Balance	$ 4,586,952	$ 5,080,081	$ 4,595,574
Contributions	4,490,682	3,347,260	3,697,533
Distributions	(3,858,888)	(4,192,345)	(3,617,099)
Shares contributed by parent company		(10,000)
Net income	309,479	361,066	403,238
Other comprehensive income	598	890	835
Ending Balance	5,528,823	4,586,952	5,080,081
General Partner's Capital Class A Common Units | Class A Common Units
Increase (Decrease) in Partners' Capital
Beginning Balance	4,201,872	4,734,873	4,248,736
Contributions	4,490,682	3,315,582	3,697,440
Distributions	(3,857,767)	(4,190,480)	(3,611,900)
Shares contributed by parent company		(10,000)
Net income	305,055	351,897	400,597
Ending Balance	5,139,842	4,201,872	4,734,873
Limited Partner's Capital
Increase (Decrease) in Partners' Capital
Beginning Balance	0	0	0
Ending Balance	0	0	0
Noncontrolling Interests In Other Partnerships
Increase (Decrease) in Partners' Capital
Beginning Balance	387,296	348,314	350,779
Contributions		31,678	93
Distributions	(1,121)	(1,865)	(5,199)
Net income	4,424	9,169	2,641
Ending Balance	390,599	387,296	348,314
Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Partners' Capital
Beginning Balance	(2,216)	(3,106)	(3,941)
Other comprehensive income	598	890	835
Ending Balance	$ (1,618)	$ (2,216)	$ (3,106)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Activities
Net income	$ 313,300	$ 362,764	$ 403,238
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	220,432	209,993	204,748
Equity in net gain on sale of interest in unconsolidated joint venture/real estate	0	0	(85,559)
Equity in net income from unconsolidated joint ventures	(14,509)	(8,841)	(4,491)
Distributions of cumulative earnings from unconsolidated joint ventures	10,430	8,621	6,269
Loss on early extinguishment of debt	0	49	7,385
Depreciable real estate reserve	0	9,998	0
Loss (gain) on sale of real estate, net	6,909	(100,190)	0
Gain on sale of discontinued operations	0	0	(117,579)
Deferred rents receivable	(23,768)	(21,378)	(23,515)
Other non-cash adjustments	(46,449)	(64,329)	(87,271)
Changes in operating assets and liabilities:
Restricted cash—operations	(11,585)	(1,182)	(4,986)
Tenant and other receivables	1,511	(9,900)	(1,238)
Deferred lease costs	(27,625)	(38,623)	(21,103)
Other assets	12,872	14,558	10,710
Accounts payable, accrued expenses, other liabilities, and security deposits	(2,937)	2,458	(4,866)
Deferred revenue and land leases payable	1,684	1,487	1,653
Net cash provided by operating activities	440,265	365,485	283,395
Investing Activities
Acquisitions of real estate property	0	(109,633)	(517,535)
Additions to land, buildings and improvements	(127,200)	(89,998)	(102,905)
Escrowed cash—capital improvements/acquisition deposits	772	593	657
Investments in unconsolidated joint venture	(25,373)	(988)	(59,400)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	1,304	28,459	0
Net proceeds from disposition of real estate/joint venture interest	42,316	238,083	237,059
Other investments	14,292	(54,475)	(16,300)
Origination of debt and preferred equity investments	(977,699)	(758,133)	(617,090)
Repayments or redemption of preferred equity investments	904,517	520,218	576,927
Net cash used in investing activities	(167,071)	(225,874)	(498,587)
Financing Activities
Proceeds from mortgages and other loans payable	50,383	360,018	221,216
Repayments of mortgages and other loans payable	(119,165)	(326,594)	(608,539)
Proceeds from revolving credit facility, term loan and senior unsecured notes	1,325,300	2,515,000	1,908,000
Repayments of revolving credit facility term loan and senior unsecured notes	(2,324,608)	(1,706,007)	(1,385,898)
Payments of debt extinguishment costs	0	0	(6,693)
Contributions from common unitholder	4,490,682	3,201,654	3,693,440
Contributions from noncontrolling interests in other partnerships	0	9,400	93
Distributions to noncontrolling interests in other partnerships	(1,121)	(1,865)	(5,199)
Distributions to common and preferred unitholder	(3,738,853)	(4,191,371)	(3,611,900)
Deferred loan costs and capitalized lease obligation	(5,058)	(9,511)	(3,681)
Other obligation related to mortgage loan participation	59,150	25,000	0
Net cash (used in) provided by financing activities	(263,290)	(124,276)	200,839
Net increase (decrease) in cash and cash equivalents	9,904	15,335	(14,353)
Cash and cash equivalents at beginning of year	50,026	34,691	49,044
Cash and cash equivalents at end of year	59,930	50,026	34,691
Supplemental Cash Flow Disclosure:
Interest paid	110,656	118,090	138,574
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Tenant improvements and capital expenditures payable	4,029	3,441	375
Deferred leasing payable	4,072	7,752	11,127
Change in fair value of hedge	206	570	519
Contributions from common unitholder	0	13,928	4,000
Distribution of land to common unitholder	8,980	0	0
Deconsolidation of a subsidiary	0	27,435	0
Issuance of SL Green common stock to a consolidated joint venture	0	10,000	0
Contribution of notes receivable from the common unit holder	0	90,000	0
Issuance of preferred units through a subsidiary	0	109,161	0
Contributions from a noncontrolling interest in other partnerships	0	22,278	0
Transfer of financing receivable to debt investment	0	0	19,675
Exchange of debt investment for equity in joint venture	68,581	0	0
Removal of fully depreciated commercial real estate properties	12,326	0	0
Settlement of related party receivable with SL Green common stock	90,000	0	0
Issuance of related party payable for SL Green common stock	$ 23,808	$ 0	$ 0

Organization and Basis of Prese

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Reckson Operating Partnership, L.P., or ROP, commenced operations on June 2, 1995. The sole general partner of ROP is Wyoming Acquisition GP LLC., or WAGP, a wholly-owned subsidiary of SL Green Operating Partnership, L.P., or the Operating Partnership. The sole limited partner of ROP is the Operating Partnership. The Operating Partnership is 95.84% owned by SL Green Realty Corp., or SL Green, as of December 31, 2016 . SL Green is a self-administered and self-managed real estate investment trust, and is the sole managing general partner of the Operating Partnership. Unless the context requires otherwise, all references to "we," "our," "us" and the "Company" means ROP and all entities owned or controlled by ROP. ROP is engaged in the acquisition, ownership, management and operation of commercial and residential real estate properties, principally office properties, and also owns land for future development, located in New York City, Westchester County, Connecticut and New Jersey, which collectively is also known as the New York Metropolitan area. SL Green, and the Operating Partnership were formed in June 1997. SL Green has qualified, and expects to qualify in the current fiscal year as a real estate investment trust, or REIT, under the Internal Revenue Code of 1986, as amended, or the Code, and operates as a self-administered, self-managed REIT. A REIT is a legal entity that holds real estate interests and, through payments of dividends to stockholders, is permitted to minimize the payment of Federal income taxes at the corporate level. On January 25, 2007, SL Green completed the acquisition of all of the outstanding shares of common stock of Reckson Associates Realty Corp., or RARC, the prior general partner of ROP. This transaction is referred to herein as the Merger. In 2015, SL Green transferred two properties and SL Green's tenancy in common interest in a fee interest with a total value of $395.0 million to ROP. Additionally, in 2015, SL Green transferred one entity that held debt investments and financing receivables with an aggregate carrying value of $1.7 billion to ROP. During 2014, SL Green transferred five properties with a total value aggregating $884.3 million to ROP. These transfers were made to further diversify ROP's portfolio. Under the business combinations guidance (Accounting Standard Codification, or ASC, 805-50), these transfers were determined to be transfers of businesses between the indirect parent company and its wholly-owned subsidiary. As such, the assets and liabilities of the properties were transferred at their carrying values and were recorded as of the beginning of the current reporting period as though the assets and liabilities had been transferred at that date. The consolidated financial statements and financial information presented for all prior periods have been retrospectively adjusted to furnish comparative information. As of December 31, 2016 , we owned the following interests in properties in the New York Metropolitan area, primarily in midtown Manhattan. Our investments in the New York Metropolitan area also include investments in Brooklyn, Westchester County, Connecticut and New Jersey, which are collectively known as the Suburban properties: Location Type Number of Properties Approximate Square Feet (unaudited) Weighted Average (1) (unaudited) Commercial: Manhattan Office 16 8,463,245 96.4 % Retail (2)(3) 5 352,892 97.6 % Fee Interest 2 197,654 100.0 % 23 9,013,791 96.5 % Suburban Office 18 3,251,000 83.2 % Retail 1 52,000 100.0 % 19 3,303,000 83.4 % Total commercial properties 42 12,316,791 93.0 % Residential: Manhattan Residential (2) — 222,855 93.1 % Total portfolio 42 12,539,646 93.0 % ____________________________________________________________________ (1) The weighted average occupancy for commercial properties represents the total occupied square feet divided by total square footage at acquisition. The weighted average occupancy for residential properties represents the total occupied units divided by total available units. (2) As of December 31, 2016 we owned a building that was comprised of approximately 270,132 square feet (unaudited) of retail space and approximately 222,855 square feet (unaudited) of residential space. For the purpose of this report, we have included the building in the number of retail properties we own. However, we have included only the retail square footage in the retail approximate square footage, and have listed the balance of the square footage as residential square footage. (3) Includes two unconsolidated joint venture retail properties at 131-137 Spring Street comprised of approximately 68,342 square feet (unaudited). As of December 31, 2016 , we also held debt, preferred equity and other investments with a book value of $2.0 billion , including $0.3 billion of debt and preferred equity investments and other financing receivables that are included in balance sheet line items other than the Debt and Preferred Equity Investments line item. Subsequent Events In January 2017, we entered into an agreement to sell 520 White Plains Road in Tarrytown, NY for a gross sale price of $21.0 million . We expect to record a $11.1 million charge in connection with the sale, which will be included in depreciable real estate reserves. The transaction is expected to close during the second quarter of 2017. At December 31, 2016, we determined that the held for sale criteria was not met for this property as it was not probable that the sale of the asset would be completed within one year.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Principles of Consolidation The consolidated financial statements include our accounts and those of our subsidiaries, which are wholly-owned or controlled by us. Entities which we do not control through our voting interest and entities which are variable interest entities, but where we are not the primary beneficiary, are accounted for under the equity method. See Note 5, "Debt and Preferred Equity Investments" and Note 6, "Investments in Unconsolidated Joint Ventures." All significant intercompany balances and transactions have been eliminated. We consolidate a variable interest entity, or VIE, in which we are considered the primary beneficiary. The primary beneficiary is the entity that has (i) the power to direct the activities that most significantly impact the entity's economic performance and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could be significant to the VIE. Included in commercial real estate properties on our consolidated balance sheets as of December 31, 2016 and 2015 are $ 1.4 billion and $ 0.3 billion, respectively, related to our consolidated VIEs. Included in mortgages and other loans payable on our consolidated balance sheets as of December 31, 2016 and 2015 are $ 494.1 million and none , respectively, related to our consolidated VIEs. A noncontrolling interest in a consolidated subsidiary is defined as the portion of the equity (net assets) in a subsidiary not attributable, directly or indirectly, to us. Noncontrolling interests are required to be presented as a separate component of equity in the consolidated balance sheet and the presentation of net income is modified to present earnings and other comprehensive income attributed to controlling and noncontrolling interests. We assess the accounting treatment for each joint venture and debt and preferred equity investment. This assessment includes a review of each joint venture or limited liability company agreement to determine the rights provided to each party and whether those rights are protective or participating. For all VIEs, we review such agreements in order to determine which party has the power to direct the activities that most significantly impact the entity's economic performance. In situations where we and our partner approve, among other things, the annual budget, receive a detailed monthly reporting package, meet on a quarterly basis to review the results of the joint venture, review and approve the joint venture's tax return before filing, and approve all leases that cover more than a nominal amount of space relative to the total rentable space at each property, we do not consolidate the joint venture as we consider these to be substantive participation rights that result in shared power of the activities that most significantly impact the performance of the joint venture. Our joint venture agreements typically contain certain protective rights such as requiring partner approval to sell, finance or refinance the property and the payment of capital expenditures and operating expenditures outside of the approved budget or operating plan. Investment in Commercial Real Estate Properties Real estate properties are presented at cost less accumulated depreciation and amortization. Costs directly related to the development or redevelopment of properties are capitalized. Ordinary repairs and maintenance are expensed as incurred; major replacements and betterments, which improve or extend the life of the asset, are capitalized and depreciated over their estimated useful lives. A property to be disposed of is reported at the lower of its carrying value or its estimated fair value, less its cost to sell. Once an asset is held for sale, depreciation expense is no longer recorded. The Company adopted ASU 2014-08 effective January 1, 2015 which raised the threshold for disposals to qualify as discontinued operations to include only dispositions that represent a strategic shift in an entity’s operations. The guidance was applied prospectively for new disposals. No properties were held for sale during 2016. The Company classified 140 Grand Street in White Plains, New York as held for sale as of September 30, 2015 and 131-137 Spring Street as of June 30, 2015 and included the results of operations in continuing operations for all periods presented. Discontinued operations included the results of operations of real estate assets sold or held for sale prior to January 1, 2015. This included 673 First Avenue, which was sold during 2014. See Note 4, "Properties Held for Sale and Dispositions." Properties are depreciated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives are as follows: Category Term Building (fee ownership) 40 years Building improvements shorter of remaining life of the building or useful life Building (leasehold interest) lesser of 40 years or remaining term of the lease Property under capital lease remaining lease term Furniture and fixtures four to seven years Tenant improvements shorter of remaining term of the lease or useful life Depreciation expense (including amortization of capital lease assets) totaled $196.2 million , $187.2 million , and $184.3 million and for the years ended December 31, 2016 , 2015 and 2014 , respectively. On a periodic basis, we assess whether there are any indications that the value of our real estate properties may be other than temporarily impaired or that their carrying value may not be recoverable. A property's value is considered impaired if management's estimate of the aggregate future cash flows (undiscounted) to be generated by the property is less than the carrying value of the property. To the extent impairment has occurred, the loss will be measured as the excess of the carrying amount of the property over the calculated fair value of the property. We also evaluate our real estate properties for potential impairment when a real estate property has been classified as held for sale. Real estate assets held for sale are valued at the lower of either their carrying value or fair value less costs to sell. We do not believe that there were any indicators of impairment at any of our consolidated properties at December 31, 2016 . During the third quarter of 2015, we recorded a $10.0 million charge in connection with the expected sale of one of our properties, which closed in the fourth quarter of 2015. This charge is included in depreciable real estate reserves in the consolidated statements of operations. We incur a variety of costs in the development and leasing of our properties. After determination is made to capitalize a cost, it is allocated to the specific component of a project that is benefited. Determination of when a development project is substantially complete and capitalization must cease involves a degree of judgment. The costs of land and building under development include specifically identifiable costs. The capitalized costs include, but are not limited to, pre-construction costs essential to the development of the property, development costs, construction costs, interest costs, real estate taxes, salaries and related costs and other costs incurred during the period of development. We consider a construction project as substantially completed and held available for occupancy upon the completion of tenant improvements, but no later than one year after major construction activity ceases. We cease capitalization on the portions substantially completed and occupied or held available for occupancy, and capitalize only those costs associated with the portions under construction. Results of operations of properties acquired are included in the consolidated statements of operations from the date of acquisition. We recognize the assets acquired, liabilities assumed (including contingencies) and any noncontrolling interests in an acquired entity at their fair values on the acquisition date. We expense transaction costs related to the acquisition of certain assets as incurred, which are included in transaction related costs on our consolidated statements of operations. In January, 2017, the FASB published ASU No. 2017-01, Business Combinations: Clarifying the Definition of a Business, which provides guidance as to whether transaction costs should be expensed or capitalized. Refer to Note 2, Accounting Standards Updates for the Company's adoption of the new guidance. When we acquire our partner's equity interest in an existing unconsolidated joint venture and gain control over the investment, we record the consolidated investment at fair value. The difference between the book value of our equity investment on the purchase date and our share of the fair value of the investment's purchase price is recorded as a purchase price fair value adjustment in our consolidated statements of operations. We allocate the purchase price of real estate to land and building (inclusive of tenant improvements) and, if determined to be material, intangibles, such as the value of above- and below-market leases and origination costs associated with the in-place leases. We depreciate the amount allocated to building (inclusive of tenant improvements) over their estimated useful lives, which generally range from three to 40 years . We amortize the amount allocated to the above- and below-market leases over the remaining term of the associated lease, which generally range from one to 14 years , and record it as either an increase (in the case of below-market leases) or a decrease (in the case of above-market leases) to rental income. We amortize the amount allocated to the values associated with in-place leases over the expected term of the associated lease, which generally ranges from one to 14 years . If a tenant vacates its space prior to the contractual termination of the lease and no rental payments are being made on the lease, any unamortized balance of the related intangible will be written off. The tenant improvements and origination costs are amortized as an expense over the remaining life of the lease (or charged against earnings if the lease is terminated prior to its contractual expiration date). We assess fair value of the leases based on estimated cash flow projections that utilize appropriate discount and capitalization rates and available market information. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. To the extent acquired leases contain fixed rate renewal options that are below-market and determined to be material, we amortize such below-market lease value into rental income over the renewal period. As of December 31, 2016 , the weighted average amortization period for above-market leases, below-market leases, and in-place lease costs is 4.1 years, 28.8 years, and 11.3 years, respectively. We recognized $20.2 million , $24.9 million , and $21.0 million of rental revenue for the years ended December 31, 2016 , 2015 and 2014 , respectively, for the amortization of aggregate below-market leases in excess of above-market leases and a reduction in lease origination costs, resulting from the allocation of the purchase price of the applicable properties. We recognized as an increase (a reduction) to interest expense the amortization of the above-market rate mortgages assumed of $0.1 million and $0.4 million for the years ended December 31, 2016 and 2015 , respectively. In March 2014, we recognized income of $0.3 million for the amortization of the remaining value of below-market rate mortgage at 16 Court Street, Brooklyn, as a result of early repayment of debt. Excluding this one-time income, we recognized as a reduction to interest expense the amortization of the above-market rate mortgages assumed of $2.1 million for the year ended December 31, 2014. The following summarizes our identified intangible assets (acquired above-market leases and in-place leases) and intangible liabilities (acquired below-market leases) as of December 31, 2016 and 2015 (in thousands): December 31, 2016 December 31, 2015 Identified intangible assets (included in other assets): Gross amount $ 311,830 $ 307,824 Accumulated amortization (253,064 ) (235,040 ) Net (1) $ 58,766 $ 72,784 Identified intangible liabilities (included in deferred revenue): Gross amount $ 524,793 $ 523,228 Accumulated amortization (368,738 ) (346,857 ) Net (1) $ 156,055 $ 176,371 ____________________________________________________________________ (1) As of December 31, 2016, no net intangible assets and no net intangible liabilities were reclassified to assets held for sale and liabilities related to assets held for sale. The estimated annual amortization of acquired above-market leases, net of acquired (below-market) leases (a component of rental revenue), for each of the five succeeding years is as follows (in thousands): 2017 $ (15,745 ) 2018 (13,628 ) 2019 (13,135 ) 2020 (12,342 ) 2021 (3,831 ) The estimated annual amortization of all other identifiable assets (a component of depreciation and amortization expense) including tenant improvements for each of the five succeeding years is as follows (in thousands): 2017 $ 14,403 2018 9,195 2019 7,519 2020 6,617 2021 3,719 Cash and Cash Equivalents We consider all highly liquid investments with maturity of three months or less when purchased to be cash equivalents. Restricted Cash Restricted cash primarily consists of security deposits held on behalf of our tenants, interest reserves, as well as capital improvement and real estate tax escrows required under certain loan agreements. Fair Value Measurements See Note 11, "Fair Value Measurements." Investment in Unconsolidated Joint Ventures We account for our investments in unconsolidated joint ventures under the equity method of accounting in cases where we exercise significant influence over, but do not control, these entities and are not considered to be the primary beneficiary. We consolidate those joint ventures that we control or which are VIEs and where we are considered to be the primary beneficiary. In all these joint ventures, the rights of the joint venture partner are both protective as well as participating. Unless we are determined to be the primary beneficiary in a VIE, these participating rights preclude us from consolidating these VIE entities. These investments are recorded initially at cost, as investments in unconsolidated joint ventures, and subsequently adjusted for equity in net income (loss) and cash contributions and distributions. Equity in net income (loss) from unconsolidated joint ventures is allocated based on our ownership or economic interest in each joint venture. When a capital event (as defined in each joint venture agreement) such as a refinancing occurs, if return thresholds are met, future equity income will be allocated at our increased economic interest. We recognize incentive income from unconsolidated real estate joint ventures as income to the extent it is earned and not subject to a clawback feature. Distributions we receive from unconsolidated real estate joint ventures in excess of our basis in the investment are recorded as offsets to our investment balance if we remain liable for future obligations of the joint venture or may otherwise be committed to provide future additional financial support. None of the joint venture debt is recourse to us. See Note 6, "Investments in Unconsolidated Joint Ventures." We assess our investments in unconsolidated joint ventures for recoverability, and if it is determined that a loss in value of the investment is other than temporary, we write down the investment to its fair value. We evaluate our equity investments for impairment based on the joint ventures' projected discounted cash flows. We do not believe that the values of any of our equity investments were impaired at December 31, 2016 . We may originate loans for real estate acquisition, development and construction, where we expect to receive some of the residual profit from such projects. When the risk and rewards of these arrangements are essentially the same as an investor or joint venture partner, we account for these arrangements as real estate investments under the equity method of accounting for investments. Otherwise, we account for these arrangements consistent with our loan accounting for our debt and preferred equity investments. Deferred Lease Costs Deferred lease costs consist of fees and direct costs incurred to initiate and renew operating leases and are amortized on a straight-line basis over the related lease term. Deferred Financing Costs Deferred financing costs represent commitment fees, legal, title and other third party costs associated with obtaining commitments for financing which result in a closing of such financing. These costs are amortized over the terms of the respective agreements. Unamortized deferred financing costs are expensed when the associated debt is refinanced or repaid before maturity. Costs incurred in seeking financing transactions, which do not close, are expensed in the period in which it is determined that the financing will not close. Deferred debt issuance costs related to a recognized debt liability are presented in the balance sheet as a direct deduction from the carrying amount of that debt liability. Revenue Recognition Rental revenue is recognized on a straight-line basis over the term of the lease. Rental revenue recognition commences when the tenant takes possession or controls the physical use of the leased space. In order for the tenant to take possession, the leased space must be substantially ready for its intended use. To determine whether the leased space is substantially ready for its intended use, management evaluates whether we are or the tenant is the owner of tenant improvements for accounting purposes. When management concludes that we are the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of the finished space, which is when such tenant improvements are substantially complete. In certain instances, when management concludes that we are not the owner (the tenant is the owner) of tenant improvements, rental revenue recognition begins when the tenant takes possession of or controls the space. When management concludes that we are the owner of tenant improvements for accounting purposes, we record amounts funded to construct the tenant improvements as a capital asset. For these tenant improvements, we record amounts reimbursed by tenants as a reduction of the capital asset. When management concludes that the tenant is the owner of tenant improvements for accounting purposes, we record our contribution towards those improvements as a lease incentive, which is included in deferred costs, net on our consolidated balance sheets and amortized as a reduction to rental revenue on a straight-line basis over the term of the lease. The excess of rents recognized over amounts contractually due pursuant to the underlying leases are included in deferred rents receivable on the consolidated balance sheets. We establish, on a current basis, an allowance for future potential tenant credit losses, which may occur against this account. The balance reflected on the consolidated balance sheets is net of such allowance. In addition to base rent, our tenants also generally will pay their pro rata share of increases in real estate taxes and operating expenses for the building over a base year. In some leases, in lieu of paying additional rent based upon increases in building operating expenses, the tenant will pay additional rent based upon increases in the wage rate paid to porters over the porters' wage rate in effect during a base year or increases in the consumer price index over the index value in effect during a base year. In addition, many of our leases contain fixed percentage increases over the base rent to cover escalations. Electricity is most often supplied by the landlord either on a sub-metered basis, or rent inclusion basis (i.e., a fixed fee is included in the rent for electricity, which amount may increase based upon increases in electricity rates or increases in electrical usage by the tenant). Base building services other than electricity (such as heat, air conditioning and freight elevator service during business hours, and base building cleaning) are typically provided at no additional cost, with the tenant paying additional rent only for services which exceed base building services or for services which are provided outside normal business hours. These escalations are based on actual expenses incurred in the prior calendar year. If the expenses in the current year are different from those in the prior year, then during the current year, the escalations will be adjusted to reflect the actual expenses for the current year. We record a gain on sale of real estate when title is conveyed to the buyer, subject to the buyer's financial commitment being sufficient to provide economic substance to the sale and provided that we have no substantial economic involvement with the buyer. Interest income on debt and preferred equity investments is accrued based on the contractual terms of the instruments and when, in the opinion of management, it is deemed collectible. Some debt and preferred equity investments provide for accrual of interest at specified rates, which differ from current payment terms. Interest is recognized on such loans at the accrual rate subject to management's determination that accrued interest is ultimately collectible, based on the underlying collateral and operations of the borrower. If management cannot make this determination, interest income above the current pay rate is recognized only upon actual receipt. Deferred origination fees, original issue discounts and loan origination costs, if any, are recognized as an adjustment to the interest income over the terms of the related investments using the effective interest method. Fees received in connection with loan commitments are also deferred until the loan is funded and are then recognized over the term of the loan as an adjustment to yield. Discounts or premiums associated with the purchase of loans are amortized or accreted into interest income as a yield adjustment on the effective interest method based on expected cash flows through the expected maturity date of the related investment. If we purchase a debt or preferred equity investment at a discount, intend to hold it until maturity and expect to recover the full value of the investment, we accrete the discount into income as an adjustment to yield over the term of the investment. If we purchase a debt or preferred equity investment at a discount with the intention of foreclosing on the collateral, we do not accrete the discount. For debt investments acquired at a discount for credit quality, the difference between contractual cash flows and expected cash flows at acquisition is not accreted. Anticipated exit fees, the collection of which is expected, are also recognized over the term of the loan as an adjustment to yield. Debt and preferred equity investments are placed on a non-accrual status at the earlier of the date at which payments become 90 days past due or when, in the opinion of management, a full recovery of interest income becomes doubtful. Interest income recognition on any non-accrual debt or preferred equity investment is resumed when such non-accrual debt or preferred equity investment becomes contractually current and performance is demonstrated to be resumed. Interest is recorded as income on impaired loans only to the extent cash is received. We may syndicate a portion of the loans that we originate or sell the loans individually. When a transaction meets the criteria for sale accounting, we derecognize the loan sold and recognize gain or loss based on the difference between the sales price and the carrying value of the loan sold. Any related unamortized deferred origination fees, original issue discounts, loan origination costs, discounts or premiums at the time of sale are recognized as an adjustment to the gain or loss on sale, which is included in investment income on the consolidated statement of operations. Any fees received at the time of sale or syndication are recognized as part of investment income. Asset management fees are recognized on a straight-line basis over the term of the asset management agreement. Allowance for Doubtful Accounts We maintain an allowance for doubtful accounts for estimated losses resulting from the inability of our tenants to make required payments. If the financial condition of a specific tenant were to deteriorate, resulting in an impairment of its ability to make payments, additional allowances may be required. Reserve for Possible Credit Losses The expense for possible credit losses in connection with debt and preferred equity investments is the charge to earnings to increase the allowance for possible credit losses to the level that we estimate to be adequate, based on Level 3 data, considering delinquencies, loss experience and collateral quality. Other factors considered include geographic trends, product diversification, the size of the portfolio and current economic conditions. Based upon these factors, we establish a provision for possible credit loss on each individual investment. When it is probable that we will be unable to collect all amounts contractually due, the investment is considered impaired. Where impairment is indicated on an investment that is held to maturity, a valuation allowance is measured based upon the excess of the recorded investment amount over the net fair value of the collateral. Any deficiency between the carrying amount of an asset and the calculated value of the collateral is charged to expense. We continue to assess or adjust our estimates based on circumstances of a loan and the underlying collateral. If additional information reflects increased recovery of our investment, we will adjust our reserves accordingly. There were no loan reserves recorded during years ended December 31, 2016 , 2015 , and 2014 . Debt and preferred equity investments held for sale are carried at the lower of cost or fair market value using available market information obtained through consultation with dealers or other originators of such investments as well as discounted cash flow models based on Level 3 data pursuant to ASC 820-10. As circumstances change, management may conclude not to sell an investment designated as held for sale. In such situations, the investment will be reclassified at its net carrying value to debt and preferred equity investments held to maturity. For these reclassified investments, the difference between the current carrying value and the expected cash to be collected at maturity will be accreted into income over the remaining term of the investment. Rent Expense Rent expense is recognized on a straight-line basis over the initial term of the lease. The excess of the rent expense recognized over the amounts contractually due pursuant to the underlying lease is included in the deferred lease payable on the consolidated balance sheets. Exchangeable Debt Instruments The initial proceeds from exchangeable debt that may be settled in cash, including partial cash settlements, are bifurcated between a liability component and an equity component associated with the embedded conversion option. The objective of the accounting guidance is to require the liability and equity components of exchangeable debt to be separately accounted for in a manner such that the interest expense on the exchangeable debt is not recorded at the stated rate of interest but rather at an effective rate that reflects the issuer's conventional debt borrowing rate at the date of issuance. We calculate the liability component of exchangeable debt based on the present value of the contractual cash flows discounted at our comparable market conventional debt borrowing rate at the date of issuance. The difference between the principal amount and the fair value of the liability component is reported as a discount on the exchangeable debt that is accreted as additional interest expense from the issuance date through the contractual maturity date using the effective interest method. A portion of this additional interest expense may be capitalized to the development and redevelopment balances qualifying for interest capitalization each period. The liability component of the exchangeable debt is reported net of discounts on our consolidated balance sheets. We calculate the equity component of exchangeable debt based on the difference between the initial proceeds received from the issuance of the exchangeable debt and the fair value of the liability component at the issuance date. The equity component is included in additional paid-in-capital, net of issuance costs, on our consolidated balance sheets. We allocate issuance costs for exchangeable debt between the liability and the equity components based on their relative values. Income Taxes SL Green is taxed as a REIT under Section 856(c) of the Code. As a REIT, SL Green generally is not subject to Federal income tax. To maintain its qualification as a REIT, SL Green must distribute at least 90% of its REIT taxable income to its stockholders and meet certain other requirements. If SL Green fails to qualify as a REIT in any taxable year, SL Green will be subject to Federal income tax on SL Green's taxable income at regular corporate rates. SL Green may also be subject to certain state, local and franchise taxes. Under certain circumstances, Federal income and excise taxes may be due on SL Green's undistributed taxable income. ROP is a disregarded entity of SL Green Operating Partnership, L.P. for federal income tax purposes, and, as a result, all income and losses of ROP are considered income and losses of SL Green Operating Partnership, L. P. No provision has been made for income taxes in the consolidated financial statements since such taxes, if any, are the responsibility of the individual partners of SL Green Operating Partnership, L.P. We follow a two-step approach for evaluating uncertain tax positions. Recognition (step one) occurs when an enterprise concludes that a tax position, based solely on its technical merits, is more-likely-than-not to be sustained upon examination. Measurement (step two) determines the amount of benefit that is more-likely-than-not to be realized upon settlement. Derecognition of a tax position that was previously recognized would occur when a company subsequently determines that a tax position no longer meets the more-likely-than-not threshold of being sustained. The use of a valuation allowance as a substitute for derecognition of tax positions is prohibited. Derivative Instruments In the normal course of business, we use a variety of commonly used derivative instruments, such as interest rate swaps, caps, collars and floors, to manage, or hedge, interest rate risk. Effectiveness is essential for those derivatives that we intend to qualify for hedge accounting. Some derivative instruments are associated with an anticipated transaction. In those cases, hedge effectiveness criteria also require that it be probable that the underlying transaction occurs. Instruments that meet these hedging criteria are formally designated as hedges at the inception of the derivative contract. To determine the fair values of derivative instruments, we use a variety of methods and assumptions that are based on market conditions and risks existing at each balance sheet date. For the majority of financial instruments including most derivatives, long-term investments and long-term debt, standard market conventions and techniques such as discounted cash flow analysis, option pricing models, replacement cost, and termination cost are used to determine fair value. All methods of assessing fair value result in a general approximation of value, and such value may never actually be realized. In the normal course of business, we are exposed to the effect of interest rate changes and limit these risks by following established risk management policies and procedures including the use of derivatives. To address exposure to interest rates, derivatives are used primarily to fix the rate on debt based on floating-rate indices and manage the cost of borrowing obligations. We use a variety of commonly used derivative products that are considered plain vanilla derivatives. These derivatives typically include interest rate swaps, caps

Property Acquisitions

Property Acquisitions	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Property Acquisitions	Property Acquisitions We did not acquire any properties during the twelve months ended December 31, 2016. 2015 Acquisition During the year ended December 31, 2016, we finalized the purchase price allocations for the following 2015 acquisition based on facts and circumstances that existed at the acquisition date for the property (in thousands): 110 Greene Street (1)(2) Acquisition Date July 2015 Ownership Type Fee Interest Property Type Office Purchase Price Allocation: Land $ 45,120 Building and building leasehold 215,470 Above-market lease value — Acquired in-place leases 8,967 Other assets, net of other liabilities — Assets acquired 269,557 Mark-to-market assumed debt — Below-market lease value (14,557 ) Derivatives — Liabilities assumed (14,557 ) Purchase price $ 255,000 Net consideration funded by us at closing, excluding consideration financed by debt $ 255,000 Equity and/or debt investment held $ — Debt assumed $ — __________________________________________________________ (1) Based on our preliminary analysis of the purchase price, we had allocated $89.3 million and $165.8 million to land and building, respectively, at 110 Greene Street. The impact to our consolidated statements of operations for the twelve months ended December 31, 2016 was an increase in rental revenue of $1.6 million for the amortization of aggregate below-market leases and an additional $3.1 million of depreciation expense. (2) We acquired a 90.0% controlling interest in this property for consideration that included the issuance of $5.0 million and $6.7 million aggregate liquidation preferences of Series P and Q Preferred Units, respectively, of limited partnership interest of the Operating Partnership and cash. 2014 Acquisitions During the year ended December 31, 2015, we finalized the purchase price allocation based on third party appraisal and additional facts and circumstances that existed at the acquisition dates for the following 2014 acquisitions (in thousands): 102 Greene (1) 635 Madison Ave (1) 115 Spring Street (1) Acquisition Date October 2014 September 2014 July 2014 Ownership Type Fee Interest Fee Interest Fee Interest Property Type Retail Land Retail Purchase Price Allocation: Land $ 8,215 $ 205,632 $ 11,078 Building and building leasehold 26,717 15,805 44,799 Above-market lease value — — — Acquired in-place lease value 1,015 17,345 2,037 Other assets, net of other liabilities 3 — — Assets acquired 35,950 238,782 57,914 Mark-to-market assumed debt — — — Below-market lease value 3,701 85,036 4,789 Liabilities assumed 3,701 85,036 4,789 Purchase price $ 32,249 $ 153,746 $ 53,125 Net consideration funded by us at closing, excluding consideration financed by debt $ 32,249 $ 153,746 $ 53,125 Equity and/or debt investment held $ — $ — $ — Debt assumed $ — $ — $ — ____________________________________________________________________ (1) Based on our preliminary analysis of the purchase price, we had allocated $11.3 million and $21.0 million to land and building, respectively, at 102 Greene Street, $153.7 million to land at 635 Madison Avenue, and $15.9 million and $37.2 million to land and building, respectively, at 115 Spring Street. The impact to our consolidated statement of operations for the year ended December 31, 2015 was $1.9 million in rental revenue for the amortization of aggregate below-market leases and $1.1 million of depreciation expense.

Property Held for Sale and Disp

Property Held for Sale and Dispositions	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Property Held for Sale and Dispositions	Property Held for Sale and Dispositions Properties Held for Sale As of December 31, 2016 , no properties in our portfolio were classified as held for sale. Property Dispositions The following table summarizes the properties sold during the years ended December 31, 2016 , 2015 and 2014 : Property Disposition Date Property Type Approximate Usable Square Feet (unaudited) Sale Price (1) (in millions) Gain (loss) on Sale (2) (in millions) 7 International Drive May 2016 Land 31 Acres $ 20.0 $ (6.9 ) 140 Grand Street (3) December 2015 Office 130,100 $ 22.4 $ (10.5 ) 131-137 Spring Street (4) August 2015 Office 68,342 $ 277.8 $ 101.1 673 First Avenue May 2014 Office 422,000 $ 145.0 $ 117.6 ____________________________________________________________________ (1) Sales price represents the actual sales price for the property or the gross asset valuation for the interest in a property. (2) The gain on sale for 131-137 Spring Street and 673 First Avenue are net of $4.1 million and $3.4 million , respectively, in employee compensation awards accrued in connection with the realization of these investment gains as a bonus to certain employees that were instrumental in realizing the gain on sale. Additionally, amounts do not include adjustments for expenses recorded in subsequent periods. (3) Gain/(loss) on sale includes a $10.0 million charge that was recorded during the third quarter of 2015. This charge is included in depreciable real estate reserves in the consolidated statement of operations. (4) We sold an 80% interest in 131-137 Spring Street and have subsequently accounted for our interest in the properties as an investment in unconsolidated joint ventures. See Note 5, "Debt, Preferred Equity and Other Investments." Discontinued Operations The Company adopted ASU 2014-08 effective January 1, 2015 which raised the threshold for disposals to qualify as discontinued operations to include only dispositions that represent a strategic shift in an entity’s operations. The guidance was applied prospectively for new disposals. As a result, the Company classified 140 Grand Street in White Plains, New York as held for sale as of September 30, 2015 and 131-137 Spring Street as of June 30, 2015, and included the results of operations in continuing operations for all periods presented. Discontinued operations included the results of operations of real estate assets sold or held for sale prior to January 1, 2015. This included 673 First Avenue, which was sold during May 2014. The following table summarizes net income from discontinued operations for the years ended December 31, 2016 , 2015 , and 2014 (in thousands): Year Ended December 31, 2016 2015 2014 Revenues Rental revenue $ — $ — $ 7,853 Escalation and reimbursement revenues — — 1,080 Other income — — — Total revenues — — 8,933 Operating expenses — — 1,222 Real estate taxes — — 1,402 Ground rent — — 3,001 Interest expense, net of interest income — — 879 Depreciation and amortization — — 433 Total expenses — — 6,937 Net income from discontinued operations $ — $ — $ 1,996

Debt and Preferred Equity Inves

Debt and Preferred Equity Investments	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Debt and Preferred Equity Investments	Debt and Preferred Equity Investments During the years ended December 31, 2016 and 2015 , our debt and preferred equity investments, net of discounts and deferred origination fees, increased $1,015 million and $781 million , respectively, due to originations, purchases, advances under future funding obligations, discount and fee amortization, and paid-in-kind interest, net of premium amortization. We recorded repayments, participations and sales of $1,045 million and $520 million during the years ended December 31, 2016 and 2015 , respectively, which offset the increases in debt and preferred equity investments. Debt Investments As of December 31, 2016 and 2015 , we held the following debt investments with an aggregate weighted average current yield of 9.34% at December 31, 2016 (in thousands): Loan Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 Carrying Value (1) Maturity Date (2) Fixed Rate Investments: Jr. Mortgage Participation/Mezzanine Loan (3) $ — $ 1,109,000 $ 193,422 $ 104,661 March 2017 Mezzanine Loan (4a) — 502,100 66,129 41,115 June 2017 Mortgage Loan (5) — — 26,311 26,262 February 2019 Mortgage Loan — — 380 513 August 2019 Loan Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 Carrying Value (1) Maturity Date (2) Mezzanine Loan — 15,000 3,500 3,500 September 2021 Mezzanine Loan (4b) — 88,466 12,692 19,936 November 2023 Mezzanine Loan (4c) — 115,000 12,925 24,916 June 2024 Mezzanine Loan — 95,000 30,000 30,000 January 2025 Mezzanine Loan — 340,000 15,000 — November 2026 Mezzanine Loan (6) — — — 72,102 Mezzanine Loan (7) — — — 49,691 Jr. Mortgage Participation (8) — — — 49,000 Other (8)(9) — — — 23,510 Other (8)(9) — — — 66,183 Total fixed rate $ — $ 2,264,566 $ 360,359 $ 511,389 Floating Rate Investments: Mortgage/Mezzanine Loan (4d)(10) 36,042 — 145,239 134,264 January 2017 Mezzanine Loan (11) — 118,949 29,998 28,551 January 2017 Mezzanine Loan (4e)(12) — 40,000 15,369 68,977 June 2017 Mortgage/Mezzanine Loan — — 32,847 — June 2017 Mortgage/Mezzanine Loan — — 22,959 22,877 July 2017 Mortgage/Mezzanine Loan — — 16,960 16,901 September 2017 Mortgage/Mezzanine Loan 3,479 — 20,423 19,282 October 2017 Mezzanine Loan — 60,000 14,957 14,904 November 2017 Mezzanine Loan (4f) — 85,000 15,141 29,505 December 2017 Mezzanine Loan (4g) — 65,000 14,656 28,563 December 2017 Mortgage/Mezzanine Loan (4h) 795 — 15,051 14,942 December 2017 Jr. Mortgage Participation — 40,000 19,913 19,846 April 2018 Mezzanine Loan — 175,000 34,844 34,725 April 2018 Mortgage/Mezzanine Loan (13) 523 20,523 10,863 31,210 August 2018 Mortgage Loan — — 19,840 — August 2018 Mezzanine Loan — 65,000 14,880 — August 2018 Mezzanine Loan — 37,500 14,648 — September 2018 Mezzanine Loan 2,324 45,025 34,502 — October 2018 Mezzanine Loan — 335,000 74,476 — November 2018 Mezzanine Loan — 33,000 26,850 26,777 December 2018 Mezzanine Loan 3,317 165,326 56,114 52,774 December 2018 Mezzanine Loan 15,794 259,229 63,137 49,625 December 2018 Mezzanine Loan 14,715 199,935 64,505 — December 2018 Mezzanine Loan — 45,000 12,104 — January 2019 Mezzanine Loan 6,383 16,383 5,410 — January 2019 Mezzanine Loan — 38,000 21,891 21,845 March 2019 Mezzanine Loan — 265,000 24,707 — April 2019 Mortgage/Jr. Mortgage Participation Loan 33,573 183,300 65,554 — August 2019 Mezzanine Loan 2,500 187,500 37,322 — September 2019 Mortgage/Mezzanine Loan 82,888 — 111,819 — September 2019 Mortgage/Mezzanine Loan 35,630 — 33,682 — January 2020 Loan Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 Carrying Value (1) Maturity Date (2) Mezzanine Loan (14) 32,502 445,483 125,911 — January 2020 Jr. Mortgage Participation/Mezzanine Loan — 30,000 15,606 — July 2021 Mezzanine Loan (15) — — — 49,751 Mezzanine Loan (15) — — — 13,731 Mezzanine Loan (16) — — — 99,530 Mortgage/Mezzanine Loan (17) — — — 94,901 Jr. Mortgage Participation/Mezzanine Loan (6) — — — 20,510 Mezzanine Loan (18) — — — 22,625 Mezzanine Loan (19) — — — 74,700 Mezzanine Loan (20) — — — 66,398 Jr. Mortgage Participation/Mezzanine Loan (8) — — — 18,395 Mezzanine Loan (21) — — — 40,346 Total floating rate $ 270,465 $ 2,955,153 $ 1,232,178 $ 1,116,455 Total $ 270,465 $ 5,219,719 $ 1,592,537 $ 1,627,844 ____________________________________________________________________ (1) Carrying value is net of discounts, premiums, original issue discounts and deferred origination fees. (2) Represents contractual maturity, excluding any unexercised options. (3) This loan was refinanced at maturity in March 2017 by us at market rates, and therefore it was not considered a troubled-debt restructuring. (4) Carrying value is net of the following amount that was participated out, which is included in other assets and other liabilities on the consolidated balance sheets as a result of the transfer not meeting the conditions for sale accounting: (a) $41.3 million , (b) $5.0 million , (c) $12.0 million , (d) $36.3 million , (e) $14.5 million , (f) $14.6 million , (g) $14.1 million , and (h) $5.1 million . (5) In September 2014, we acquired a $26.4 million mortgage loan at a $0.2 million discount and a $5.7 million junior mortgage participation at a $5.7 million discount. The junior mortgage participation was a nonperforming loan at acquisition and is currently on non-accrual status. (6) This loan was repaid in July 2016. (7) In April 2016 we executed a purchase option to acquire a 20% interest in the underlying asset at a previously agreed upon purchase option valuation, and our mezzanine loan was simultaneously repaid. (8) This loan was repaid in March 2016. (9) This loan was collateralized by defeasance securities. (10) This loan was refinanced at maturity in January 2017 by us at market rates, and therefore it was not considered a troubled-debt restructuring. (11) This loan was extended in January 2017. (12) In March 2016, the mortgage was sold. (13) In January 2016, the loans were modified. In March 2016, the mortgage was sold. (14) $66.1 million of outstanding principal was syndicated in February 2017. (15) This loan was repaid in December 2016. (16) This loan was repaid in November 2016. (17) This loan was repaid in September 2016. (18) This loan was repaid in June 2016. (19) This loan was repaid in May 2016. (20) In March 2016, we contributed our interest in the loan in exchange for a joint venture interest which is now accounted for under the equity method of accounting. It is included in unconsolidated joint ventures on the consolidated balance sheets. (21) This loan was repaid in February 2016. Preferred Equity Investments As of December 31, 2016 and 2015 , we held the following preferred equity investments with an aggregate weighted average current yield of 8.16% at December 31, 2016 (in thousands): Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 (1) Mandatory Redemption (2) Preferred Equity $ — $ 71,486 $ 9,982 $ 9,967 March 2018 Preferred Equity — 58,786 37,893 32,209 November 2018 $ — $ 130,272 $ 47,875 $ 42,176 ____________________________________________________________________ (1) Carrying value is net of deferred origination fees. (2) Represents contractual maturity, excluding any unexercised extension options. The following table is a rollforward of our total loan loss reserves at December 31, 2016 , 2015 and 2014 (in thousands): Year Ended December 31, 2016 2015 2014 Balance at beginning of year $ — $ — $ 1,000 Expensed — — — Recoveries — — — Charge-offs and reclassifications — — (1,000 ) Balance at end of period $ — $ — $ — At December 31, 2016 , 2015 and 2014 , all debt and preferred equity investments were performing in accordance with the terms of the relevant investments, with the exception of the junior mortgage participation acquired in September 2014, which has a carrying value of zero discussed in subnote 4 of the Debt Investments table above. We have determined that we have one portfolio segment of financing receivables at December 31, 2016 and 2015 comprising commercial real estate which is primarily recorded in debt and preferred equity investments. Included in other assets is an additional amount of financing receivables totaling $144.5 million and $168.3 million at December 31, 2016 and 2015 , respectively. No financing receivables were 90 days past due at December 31, 2016 .

Investments in Unconsolidated J

Investments in Unconsolidated Joint Ventures (Notes)	12 Months Ended
	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Joint Ventures	6. Investments in Unconsolidated Joint Ventures We have investments in several real estate joint ventures with various partners. As of December 31, 2016 none of our investments in unconsolidated joint ventures are VIEs. The table below provides general information on each of our joint ventures as of December 31, 2016 : Property Partner Ownership Interest (1) Economic Interest (1) Approximate Square Feet Acquisition Date (2) Acquisition Price (2) (in thousands) 131-137 Spring Street Invesco Real Estate 20.00% 20.00% 68,342 August 2015 $ 277,750 76 11th Avenue (3) Oxford/Vornado 33.33% 35.09% 764,000 March 2016 138,240 (1) Ownership interest and economic interest represent the Company's interests in the joint venture as of December 31, 2016 . Changes in ownership or economic interests within the current year are disclosed in the notes below. (2) Acquisition date and price represent the date on which the Company initially acquired an interest in the joint venture and the actual or implied gross purchase price for the joint venture on that date. Acquisition date and price are not adjusted for subsequent acquisitions or dispositions of interest. (3) The joint venture owns two mezzanine notes secured by interests in the entity that owns 76 11th Avenue. The difference between our ownership interest and our economic interest results from our right to 50% of the total exit fee while each of our partners is entitled to receive 25% of the total exit fee and our right to 38% of the total extension fee while each of our partners is entitled to receive 31% of the total extension fee. Acquisition, Development and Construction Arrangement Based on the characteristics of the following arrangements, which are similar to those of an investment, combined with the expected residual profit of not greater than 50% , we have accounted for these debt and preferred equity investments under the equity method. As of December 31, 2016 and 2015 , the carrying value for acquisition, development and construction arrangements were as follows (in thousands): Loan Type December 31, 2016 December 31, 2015 Maturity Date Mezzanine Loan and Preferred Equity (1) $ 100,000 $ 99,936 March 2017 Mezzanine Loan (2) 24,542 — July 2036 $ 124,542 $ 99,936 (1) This loan was extended in March 2017. (2) The Company has the ability to convert this loan into an equity position starting in 2021 and the borrower is able to force this conversion in 2024. Sale of Joint Venture Interest or Property We did not sell any joint venture interest or property during the year ended December 31, 2016 . Joint Venture Mortgages and Other Loans Payable We generally finance our joint ventures with non-recourse debt. In certain cases we have provided guarantees or master leases for tenant space, which terminate upon the satisfaction of specified circumstances or repayment of the underlying loans. The first mortgage notes and other loans payable collateralized by the respective joint venture properties and assignment of leases at December 31, 2016 and December 31, 2015 , respectively, are as follows (amounts in thousands): Property Maturity Date Interest Rate (1) December 31, 2016 December 31, 2015 Floating Rate Debt: 131-137 Spring Street August 2020 2.03 % $ 141,000 $ 141,000 Total joint venture mortgages and other loans payable $ 141,000 $ 141,000 Deferred financing costs, net (3,970 ) (5,077 ) Total joint venture mortgages and other loans payable, net $ 137,030 $ 135,923 (1) Effective weighted average interest rate for the year ended December 31, 2016 , taking into account interest rate hedges in effect during the period. The combined balance sheets for the unconsolidated joint ventures, at December 31, 2016 and December 31, 2015 are as follows (in thousands): December 31, 2016 December 31, 2015 Assets Commercial real estate property, net $ 279,451 $ 285,689 Debt and preferred equity investments, net 273,749 99,936 Other assets 18,922 16,897 Total assets $ 572,122 $ 402,522 Liabilities and members' equity Mortgages and other loans payable, net $ 137,030 $ 135,923 Other liabilities 22,185 25,462 Members' equity 412,907 241,137 Total liabilities and members' equity $ 572,122 $ 402,522 Company's investments in unconsolidated joint ventures $ 174,127 $ 100,192 The combined statements of operations for the unconsolidated joint ventures for the years ended December 31, 2016 , 2015 , and 2014 are as follows (in thousands): Year Ended December 31, 2016 2015 2014 Total revenues $ 38,524 $ 19,855 $ 7,121 Operating expenses 1,238 1,686 59 Real estate taxes 1,192 1,262 — Interest expense, net of interest income 2,895 1,070 — Amortization of deferred financing costs 1,108 462 — Transaction related costs — 5,262 181 Depreciation and amortization 8,404 3,207 — Total expenses $ 14,837 $ 12,949 $ 240 Net income $ 23,687 $ 6,906 $ 6,881 Company's equity in net income from unconsolidated joint ventures 14,509 8,841 4,491

Mortgages and Other Loans Payab

Mortgages and Other Loans Payable	12 Months Ended
	Dec. 31, 2016
Mortgage Note and Other Loans Payable
Mortgages and Other Loans Payable	Mortgages and Other Loans Payable The first mortgages and other loans payable collateralized by the respective properties and assignment of leases at December 31, 2016 and 2015 , respectively, were as follows (amounts in thousands): Property Maturity Date Interest Rate (1) December 31, 2016 December 31, 2015 Fixed Rate Debt: 919 Third Avenue (2) June 2023 5.12 % $ 500,000 $ 500,000 Floating Rate Debt: Master Repurchase Agreement July 2018 3.04 % $ 184,642 $ 253,424 Total mortgages and other loans payable $ 684,642 $ 753,424 Deferred financing costs, net of amortization (8,574 ) (7,696 ) Total fixed and floating rate debt $ 676,068 $ 745,728 ____________________________________________________________________ (1) Effective weighted average interest rate for the year ended December 31, 2016 . (2) We own a 51.0% controlling interest in the joint venture that is the borrower on this loan. Master Repurchase Agreement In July 2016, we entered into a restated Master Repurchase Agreement, or MRA, which provides us with the ability to sell certain debt investments with a simultaneous agreement to repurchase the same at a certain date or on demand. The MRA has a maximum facility capacity of $300.0 million and bears interest ranging from 225 and 400 basis points over 30-day LIBOR depending on the pledged collateral. Since December 6, 2015, we have been required to pay monthly in arrears a 25 basis point fee on the excess of $150.0 million over the average daily balance during the period if the average daily balance is less than $150.0 million . We seek to mitigate risks associated with our repurchase agreement by managing the credit quality of our assets, early repayments, interest rate volatility, liquidity, and market value. The margin call provisions under our repurchase facility permit valuation adjustments based on capital markets activity, and are not limited to collateral-specific credit marks. To monitor credit risk associated with our debt investments, our asset management team regularly reviews our investment portfolio and is in contact with our borrowers in order to monitor the collateral and enforce our rights as necessary. The risk associated with potential margin calls is further mitigated by our ability to recollateralize the facility with additional assets from our portfolio of debt investments, our ability to satisfy margin calls with cash or cash equivalents and access to additional liquidity through the 2012 credit facility, as defined below. At December 31, 2016 and 2015 , the gross book value of the properties and debt and preferred equity investments collateralizing the mortgages and other loans payable, not including assets held for sale, was approximately $1.7 billion and $2.0 billion , respectively.

Corporate Indebtedness

Corporate Indebtedness	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Corporate Indebtedness	Corporate Indebtedness 2012 Credit Facility In August 2016, we entered into an amendment to the credit facility that was originally entered into by the Company in November 2012, referred to as the 2012 credit facility. As of December 31, 2016 , the 2012 credit facility, as amended, consisted of a $1.6 billion revolving credit facility and a $1.2 billion term loan, with a maturity date of March 29, 2019 and June 30, 2019, respectively. The revolving credit facility has an as-of-right extension to March 29, 2020. We also have an option, subject to customary conditions, to increase the capacity under the revolving credit facility to $3.0 billion at any time prior to the maturity date for the revolving credit facility without the consent of existing lenders, by obtaining additional commitments from our existing lenders and other financial institutions. As of December 31, 2016 , the 2012 credit facility bore interest at a spread over LIBOR ranging from (i) 87.5 basis points to 155 basis points for loans under the revolving credit facility and (ii) 95 basis points to 190 basis points for loans under the term loan facility, in each case based on the credit rating assigned to the senior unsecured long term indebtedness of ROP. At December 31, 2016 , the applicable spread was 125 basis points for the revolving credit facility and 140 basis points for the term loan facility. At December 31, 2016 , the effective interest rate was 1.78% for the revolving credit facility and 1.96% for the term loan facility. We are required to pay quarterly in arrears a 12.5 basis points to 30 basis point facility fee on the total commitments under the revolving credit facility based on the credit rating assigned to the senior unsecured long term indebtedness of ROP. As of December 31, 2016 , the facility fee was 25 basis points . As of December 31, 2016 , we had $56.5 million of outstanding letters of credit, zero drawn under the revolving credit facility and $1.2 billion outstanding under the term loan facility, with total undrawn capacity of $1.5 billion under the 2012 credit facility. At December 31, 2016 and December 31, 2015 , the revolving credit facility had a carrying value of $(6.3) million , representing deferred financing costs presented within other liabilities, and $985.1 million , respectively, net of deferred financing costs. At December 31, 2016 and December 31, 2015 , the term loan facility had a carrying value of $1.2 billion and $929.5 million , respectively, net of deferred financing costs. We, SL Green and the Operating Partnership are all borrowers jointly and severally obligated under the 2012 credit facility. None of SL Green's other subsidiaries are obligors under the 2012 credit facility. The 2012 credit facility includes certain restrictions and covenants (see Restrictive Covenants below). Senior Unsecured Notes The following table sets forth our senior unsecured notes and other related disclosures as of December 31, 2016 and 2015 , respectively, by scheduled maturity date (dollars in thousands): Issuance December 31, 2016 December 31, 2016 December 31, 2015 Coupon (1) Effective Rate Term (in Years) Maturity Date August 5, 2011 (2) $ 250,000 $ 249,880 $ 249,810 5.00 % 5.00 % 7 August 2018 March 16, 2010 (2) 250,000 250,000 250,000 7.75 % 7.75 % 10 March 2020 November 15, 2012 (2) 200,000 200,000 200,000 4.50 % 4.50 % 10 December 2022 December 17, 2015 (2) 100,000 100,000 100,000 4.27 % 4.27 % 10 December 2025 March 31, 2006 (3) — — 255,296 $ 800,000 $ 799,880 $ 1,055,106 Deferred financing costs, net (4,620 ) (5,303 ) $ 800,000 $ 795,260 $ 1,049,803 ______________________________________________________________________ (1) Interest on the senior unsecured notes is payable semi-annually with principal and unpaid interest due on the scheduled maturity dates. (2) Issued by SL Green, the Operating Partnership and ROP, as co-obligors. (3) This note was repaid in March 2016. ROP also provides a guaranty of the Operating Partnership's obligations under its 3.00% Exchangeable Senior Notes due 2017. Restrictive Covenants The terms of the 2012 credit facility, as amended, and certain of our senior unsecured notes include certain restrictions and covenants which may limit, among other things, SL Green's ability to pay dividends, make certain types of investments, incur additional indebtedness, incur liens and enter into negative pledge agreements and dispose of assets, and which require compliance with financial ratios relating to the maximum ratio of total indebtedness to total asset value, a minimum ratio of EBITDA to fixed charges, a maximum ratio of secured indebtedness to total asset value and a maximum ratio of unsecured indebtedness to unencumbered asset value. The dividend restriction referred to above provides that SL Green will not during any time when a default is continuing, make distributions with respect to SL Green's common stock or other equity interests, except to enable SL Green to continue to qualify as a REIT for Federal income tax purposes. As of December 31, 2016 and 2015 , we were in compliance with all such covenants. Principal Maturities Combined aggregate principal maturities of our mortgage and other loans payable, 2012 credit facility and senior unsecured notes as of December 31, 2016 , including as-of-right extension options and put options, were as follows (in thousands): Scheduled Principal Revolving Unsecured Term Loan Senior Total 2017 $ — $ — $ — $ — $ — $ — 2018 — 184,642 — — 250,000 $ 434,642 2019 — — — 1,183,000 — $ 1,183,000 2020 — — — — 250,000 $ 250,000 2021 — — — — — $ — Thereafter — 500,000 — — 300,000 $ 800,000 $ — $ 684,642 $ — $ 1,183,000 $ 800,000 $ 2,667,642 Consolidated interest expense, excluding capitalized interest, was comprised of the following (in thousands): Year Ended December 31, 2016 2015 2014 Interest expense before capitalized interest $ 110,393 $ 120,467 $ 133,180 Interest capitalized (1,171 ) (1,107 ) (3,753 ) Interest income (14 ) (18 ) (71 ) Interest expense, net $ 109,208 $ 119,342 $ 129,356

Preferred Units

Preferred Units	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Preferred Units	Preferred Units Through a consolidated subsidiary, we have authorized up to 109,161 3.5% Series A Preferred Units of limited partnership interest, or the Subsidiary Series A Preferred Units, with a liquidation preference of $1,000.00 per unit. In August 2015, the Company issued 109,161 Subsidiary Series A Preferred Units in conjunction with an acquisition. The Subsidiary Series A Preferred unitholders receive annual dividends of $35.00 per unit paid on a quarterly basis and dividends are cumulative, subject to certain provisions. The Subsidiary Series A Preferred Units can be redeemed at any time, at the option of the unitholder, either for cash or are convertible on a one-for-one basis, into the Series B Preferred Units of limited partnership interest, or the Subsidiary Series B Preferred Units. The Subsidiary Series B Preferred Units can be converted at any time, at the option of the unitholder, into a number of common stock equal to 6.71348 shares of SL Green common stock for each Subsidiary Series B Preferred Unit. As of December 31, 2016 , no Subsidiary Series B Preferred Units have been issued. ASC 815 Derivatives and Hedging requires bifurcation of certain embedded derivative instruments, such as conversion features in convertible equity instruments, and their measurement at fair value for accounting purposes. The conversion feature embedded in the Subsidiary Series A Preferred Units was evaluated, and it was determined that the conversion feature should be bifurcated from its host instrument and accounted for as a freestanding derivative. The derivative is reported as a derivative liability in accrued interest and other liabilities on the accompanying consolidated balance sheet and is adjusted to its fair value at each reporting date, with a corresponding adjustment to interest expense, net of interest income. The embedded derivative for the Subsidiary Series A Preferred Units was initially recorded at a fair value of zero on July 22, 2015, the date of issuance. At December 31, 2016 , the carrying amount of the derivative was adjusted to its fair value of zero , with a corresponding adjustment to preferred units and interest expense, net of interest income.

Partners' Capital

Partners' Capital	12 Months Ended
	Dec. 31, 2016
Partners' Capital Notes [Abstract]
Partners' Capital	Partners' Capital Since consummation of the Merger on January 25, 2007, the Operating Partnership has owned all the economic interests in ROP either by direct ownership or by indirect ownership through our general partner, which is its wholly-owned subsidiary. Intercompany transactions between SL Green and ROP are generally recorded as contributions and distributions.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We are required to disclose fair value information with regard to our financial instruments, whether or not recognized in the consolidated balance sheets, for which it is practical to estimate fair value. The FASB guidance defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. We measure and/or disclose the estimated fair value of financial assets and liabilities based on a hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity and the reporting entity’s own assumptions about market participant assumptions. This hierarchy consists of three broad levels: Level 1 - quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity can access at the measurement date; Level 2 - inputs other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly; and Level 3 - unobservable inputs for the asset or liability that are used when little or no market data is available. We follow this hierarchy for our assets and liabilities measured at fair value on a recurring and nonrecurring basis. In instances in which the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level of input that is significant to the fair value measurement in its entirety. Our assessment of the significance of the particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. We determine other than temporary impairment in real estate investments and debt and preferred equity investments, including intangibles utilizing cash flow projections that apply, among other things, estimated revenue and expense growth rates, discount rates and capitalization rates, which are classified as Level 3 inputs. The fair value of derivative instruments is based on current market data received from financial sources that trade such instruments and are based on prevailing market data and derived from third party proprietary models based on well-recognized financial principles and reasonable estimates about relevant future market conditions, which are classified as Level 2 inputs. The financial assets and liabilities that are not measured at fair value on our consolidated balance sheets include cash and cash equivalents, restricted cash, accounts receivable, accounts payable and accrued expenses, debt and preferred equity investments, mortgages and other loans payable and other secured and unsecured debt. The carrying amount of cash and cash equivalents, restricted cash, accounts receivable, and accounts payable and accrued expenses reported in our consolidated balance sheets approximates fair value due to the short term nature of these instruments. The fair value of debt and preferred equity investments, which is classified as Level 3, is estimated by discounting the future cash flows using current interest rates at which similar loans with the same maturities would be made to borrowers with similar credit ratings. The fair value of borrowings, which is classified as Level 3, is estimated by discounting the contractual cash flows of each debt instrument to their present value using adjusted market interest rates, which is provided by a third-party specialist. The following table provides the carrying value and fair value of these financial instruments as of December 31, 2016 and 2015 (in thousands): December 31, 2016 December 31, 2015 Carrying Value (1) Fair Value Carrying Value (1) Fair Value Debt and preferred equity investments (2) $ 1,640,412 (3) $ 1,670,020 (3) Fixed rate debt $ 2,099,880 $ 2,183,042 $ 1,585,106 $ 1,663,078 Variable rate debt 567,642 580,083 2,150,424 2,164,673 $ 2,667,522 $ 2,763,125 $ 3,735,530 $ 3,827,751 ______________________________________________________________________ (1) Amounts exclude net deferred financing costs. (2) Excludes investment with a book value of $174.1 million and $100.2 million as of December 31, 2016 and 2015 , respectively, which we accounted for under the equity method accounting as a result of meeting the criteria of a real estate investment under the guidance for Acquisition, Development and Construction arrangements, and other investments with a book value of $144.5 million and $168.3 million as of December 31, 2016 and 2015 , respectively. (3) At December 31, 2016 , debt and preferred equity investments had an estimated fair value ranging between $1.6 billion and $1.8 billion . At December 31, 2015 , debt and preferred equity investments had an estimated fair value ranging between $1.7 billion and $1.8 billion . Disclosure about fair value of financial instruments was based on pertinent information available to us as of December 31, 2016 and 2015 . Although we are not aware of any factors that would significantly affect the reasonable fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since that date and current estimates of fair value may differ significantly from the amounts presented herein.

Financial Instruments_ Derivati

Financial Instruments: Derivatives and Hedging	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments: Derivatives and Hedging	Financial Instruments: Derivatives and Hedging In the normal course of business, we use a variety of commonly used derivative instruments, such as interest rate swaps, caps, collar and floors, to manage, or hedge interest rate risk. We hedge our exposure to variability in future cash flows for forecasted transactions in addition to anticipated future interest payments on existing debt. We recognize all derivatives on the balance sheets at fair value. Derivatives that are not hedges are adjusted to fair value through earnings. If a derivative is a hedge, depending on the nature of the hedge, changes in the fair value of the derivative will either be offset against the change in fair value of the hedge asset, liability, or firm commitment through earnings, or recognized in other comprehensive income until the hedged item is recognized in earnings. The ineffective portion of a derivative's change in fair value will be immediately recognized in earnings. Reported net income and equity may increase or decrease prospectively, depending on future levels of interest rates and other variables affecting the fair values of derivative instruments and hedged items, but will have no effect on cash flows. Currently, all of our designated derivative instruments are effective hedging instruments. As of December 31, 2016 , the Company had not designated any interest rate swap agreements on any debt investment. Gains and losses on terminated hedges are included in accumulated other comprehensive loss, and are recognized into earnings over the term of the related senior unsecured notes. As of December 31, 2016 and 2015 , the deferred net losses from these terminated hedges, which are included in accumulated other comprehensive loss relating to net unrealized loss on derivative instruments, was approximately $1.6 million and $2.0 million , respectively. Over time, the realized and unrealized gains and losses held in accumulated other comprehensive loss will be reclassified into earnings as an adjustment to interest expense in the same periods in which the hedged interest payments affect earnings. We estimate that approximately $0.4 million of the current balance held in accumulated other comprehensive loss will be reclassified into interest expense within the next 12 months. The following table presents the effect of our derivative financial instruments that are designated and qualify as hedging instruments on the consolidated statements of operations for the years ended December 31, 2016 , 2015 , and 2014 , respectively (in thousands): Amount of Loss Recognized in Other Comprehensive Loss (Effective Portion) Location of Loss Reclassified from Accumulated Other Comprehensive Loss into Income Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion) Location of Gain Recognized in Income on Derivative Amount of Gain Recognized into Income (Ineffective Portion) Year Ended December 31, Year Ended December 31, Year Ended December 31, Derivative 2016 2015 2014 2016 2015 2014 2016 2015 2014 Interest Rate Swap $ (13 ) $ (109 ) $ (135 ) Interest expense $ 611 $ 999 $ 970 Interest expense $ 3 $ 3 $ 4

Rental Income

Rental Income	12 Months Ended
	Dec. 31, 2016
Leases [Abstract]
Rental Income	Rental Income We are the lessor and the sublessor to tenants under operating leases with expiration dates ranging from January 1, 2016 to 2039. The minimum rental amounts due under the leases are generally either subject to scheduled fixed increases or adjustments. The leases generally also require that the tenants reimburse us for increases in certain operating costs and real estate taxes above their base year costs. Approximate future minimum rents to be received over the next five years and thereafter for non-cancelable operating leases in effect at December 31, 2016 for the consolidated properties, including consolidated joint venture properties, are as follows (in thousands): 2017 $ 622,264 2018 602,291 2019 567,694 2020 501,107 2021 447,588 Thereafter 2,173,526 $ 4,914,470

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Cleaning/ Security/ Messenger and Restoration Services Alliance Building Services, or Alliance, and its affiliates are partially owned by Gary Green, a son of Stephen L. Green, the chairman of SL Green's board of directors, and provide services to certain properties owned by us. Alliance’s affiliates include First Quality Maintenance, L.P., or First Quality, Classic Security LLC, Bright Star Couriers LLC and Onyx Restoration Works, and provide cleaning, extermination, security, messenger, and restoration services, respectively. In addition, First Quality has the non-exclusive opportunity to provide cleaning and related services to individual tenants at our properties on a basis separately negotiated with any tenant seeking such additional services. The Service Corporation has entered into an arrangement with Alliance whereby it will receive a profit participation above a certain threshold for services provided by Alliance to certain tenants at certain buildings above the base services specified in their lease agreements. Income earned from profit participation, which is included in other income on the consolidated statements of operations, was $3.3 million , $3.3 million and $3.3 million for the years ended December 31, 2016 , 2015 and 2014 respectively. We also recorded expenses, inclusive of capitalized expenses, of $8.1 million , $9.9 million and $9.1 million for the years ended December 31, 2016 , 2015 and 2014 respectively, for these services (excluding services provided directly to tenants). Allocated Expenses from SL Green Property operating expenses include an allocation of salary and other operating costs from SL Green based on square footage of the related properties. Such amount was approximately $11.5 million , $10.4 million and $9.8 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. Insurance We obtain insurance coverage through an insurance program administered by SL Green. In connection with this program, we incurred insurance expense of approximately $5.9 million , $6.6 million and $6.4 million for the years ended December 31, 2016 , 2015 and 2014 respectively. Related Party Receivable from SL Green On July 22, 2015, our parent company issued a promissory note to us in the amount of $90.0 million , which bore interest at an annual rate of 6.0% , compounded quarterly, and matured on July 22, 2017. The promissory note was settled in August 2016.

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	Benefit Plans The building employees are covered by multi-employer defined benefit pension plans and post-retirement health and welfare plans. We participate in the Building Service 32BJ, or Union, Pension Plan and Health Plan. The Pension Plan is a multi-employer, non-contributory defined benefit pension plan that was established under the terms of collective bargaining agreements between the Service Employees International Union, Local 32BJ, the Realty Advisory Board on Labor Relations, Inc. and certain other employees. This Pension Plan is administered by a joint board of trustees consisting of union trustees and employer trustees and operates under employer identification number 13-1879376. The Pension Plan year runs from July 1 to June 30. Employers contribute to the Pension Plan at a fixed rate on behalf of each covered employee. Separate actuarial information regarding such pension plans is not made available to the contributing employers by the union administrators or trustees, since the plans do not maintain separate records for each reporting unit. However, on September 30, 2014, and September 28, 2015, and September 28, 2016, the actuary certified that for the plan years beginning July 1, 2014, July 1, 2015, and July 1, 2016, respectively, the Pension Plan was in critical status under the Pension Protection Act of 2006. The Pension Plan trustees adopted a rehabilitation plan consistent with this requirement. No surcharges have been paid to the Pension Plan as of December 31, 2016 . For the the Pension Plan years ended June 30, 2016, 2015, and 2014, the plan received contributions from employers totaling $249.5 million, $221.9 million , and $226.7 million , respectively. Our contributions to the Pension Plan represent less than 5.0% of total contributions to the plan. The Health Plan was established under the terms of collective bargaining agreements between the Union, the Realty Advisory Board on Labor Relations, Inc. and certain other employers. The Health Plan provides health and other benefits to eligible participants employed in the building service industry who are covered under collective bargaining agreements, or other written agreements, with the Union. The Health Plan is administered by a Board of Trustees with equal representation by the employers and the Union and operates under employer identification number 13-2928869. The Health Plan receives contributions in accordance with collective bargaining agreements or participation agreements. Generally, these agreements provide that the employers contribute to the Health Plan at a fixed rate on behalf of each covered employee. For the Health plan years ended, June 30, 2016, 2015 and 2014, the plan received contributions from employers totaling $1.2 billion , $1.1 billion and $1.0 billion , respectively. Our contributions to the Health Plan represent less than 5.0% of total contributions to the plan. Contributions we made to the multi-employer plans for the years ended December 31, 2016 , 2015 and 2014 are included in the table below (in thousands): Year Ended December 31, 2016 2015 2014 Pension Plan $ 2,219 $ 1,533 $ 1,529 Health Plan 6,366 4,843 4,585 Other plans 902 3,300 3,181 Total plan contributions $ 9,487 $ 9,676 $ 9,295

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings As of December 31, 2016 , we were not involved in any material litigation nor, to management's knowledge, was any material litigation threatened against us or our portfolio which if adversely determined could have a material adverse impact on us. Guarantees During the year ended December 31, 2015 , Belmont Insurance Company, or Belmont, a New York licensed captive insurance company and an affiliate of SL Green, became a member of the Federal Home Loan Bank of New York, or FHLBNY. As a member, Belmont could borrow funds from the FHLBNY in the form of secured advances. As of December 31, 2016 , certain commercial real estate properties and debt and preferred equity investments of the Company were pledged as collateral to secure advances under the FHLBNY facility. Belmont’s membership terminated in February, 2017 at which point Belmont repaid all funds borrowed thereby terminating any exposure to the Company. The Company incurred approximately $4.8 million of costs in conjunction with pledging assets as collateral under the FHLBNY. These costs were reimbursed to the Company by Belmont. Environmental Matters Our management believes that the properties are in compliance in all material respects with applicable Federal, state and local ordinances and regulations regarding environmental issues. Management is not aware of any environmental liability that it believes would have a materially adverse impact on our financial position, results of operations or cash flows. Management is unaware of any instances in which it would incur significant environmental cost if any of our properties were sold. Ground Leases Arrangements The property located at 711 Third Avenue operates under an operating sub-lease, which expires in 2083. The ground rent was reset in July 2011. Following the reset, we are responsible for ground rent payments of $5.3 million annually through July 2016 and then $5.5 million annually thereafter on the 50% portion of the fee that we do not own. The property located at 461 Fifth Avenue operates under a ground lease ( $2.1 million of ground rent annually) with an expiration date of 2027 and two options to renew for an additional 21 years each, followed by a third option for 15 years. We also have an option to purchase the fee position for a fixed price on a specific date. The property located at 625 Madison Avenue operates under a ground lease ( $4.6 million of ground rent annually) with an expiration date of 2022 and two options to renew for an additional 23 years. The property located at 1185 Avenue of the Americas operates under a ground lease ( $6.9 million of ground rent annually) with an expiration date of 2043 and an option to renew for an additional 23 years. The property located at 919 Third Avenue operates under a ground lease ( $0.9 million of ground rent annually) with an expiration date of 2066. The fee interest in the land at 919 Third Avenue is owned by SL Green. The property located at 1055 Washington Boulevard operates under a ground lease ( $0.6 million of ground rent annually) with an expiration date of 2090. The following is a schedule of future minimum lease payments under non-cancellable operating leases with initial terms in excess of one year as of December 31, 2016 (in thousands): Non-cancellable operating leases 2017 $ 20,586 2018 20,586 2019 20,586 2020 20,586 2021 20,736 Thereafter 308,202 Total minimum lease payments $ 411,282

Quarterly Financial Data of the

Quarterly Financial Data of the Company (unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data of the Company (unaudited)	Quarterly Financial Data of the Company (unaudited) Summarized quarterly financial data for the years ended December 31, 2016 and 2015 , was as follows (in thousands): 2016 Quarter Ended December 31 September 30 June 30 March 31 Total revenues $ 232,658 $ 271,336 $ 231,758 $ 239,664 Income from continuing operations before equity in net income from unconsolidated joint ventures, and loss on sale of real estate $ 66,056 $ 98,647 $ 71,254 $ 69,743 Equity in net income from unconsolidated joint ventures 4,110 4,276 3,666 2,457 Loss on sale of real estate (10 ) — (6,899 ) — Net income 70,156 102,923 68,021 72,200 Net income attributable to noncontrolling interests in other partnerships (1,071 ) (1,279 ) (2,062 ) (12 ) Preferred units dividend (956 ) (955 ) (955 ) (955 ) Net income attributable to ROP common unitholder $ 68,129 $ 100,689 $ 65,004 $ 71,233 2015 Quarter Ended December 31 September 30 June 30 March 31 Total revenues $ 238,283 $ 237,651 $ 234,631 $ 214,668 Income from continuing operations before equity in net income from unconsolidated joint ventures, (loss) gain on sale of real estate, depreciable real estate reserves, unrealized gain (loss) on embedded derivative and loss on extinguishment of debt $ 69,152 $ 65,541 $ 76,236 $ 52,851 Equity in net income from unconsolidated joint ventures 2,265 2,296 2,153 2,127 (Loss) gain on sale of real estate (879 ) 101,069 — — Depreciable real estate reserves — (9,998 ) — — Unrealized gain (loss) on embedded derivative 1,800 (1,800 ) — — Loss on extinguishment of debt — — — (49 ) Net income 72,338 157,108 78,389 54,929 Net income attributable to noncontrolling interests in other partnerships (1,946 ) (293 ) (6,380 ) (550 ) Preferred units dividend (955 ) (743 ) — — Net income attributable to ROP common unitholder $ 69,437 $ 156,072 $ 72,009 $ 54,379

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment Information	Segment Information We are engaged in acquiring, owning, managing and leasing commercial properties in Manhattan, Brooklyn, Westchester County, Connecticut and New Jersey and have two reportable segments, real estate and debt and preferred equity investments. We evaluate real estate performance and allocate resources based on earnings contribution to income from continuing operations. The primary sources of revenue are generated from tenant rents and escalations and reimbursement revenue. Real estate property operating expenses consist primarily of security, maintenance, utility costs, real estate taxes and ground rent expense (at certain applicable properties). See Note 5, "Debt and Preferred Equity Investments," for additional details on our debt and preferred equity investments. Selected results of operations for the years ended December 31, 2016 , 2015 and 2014 and selected asset information as of December 31, 2016 and 2015 , regarding our operating segments are as follows (in thousands): Real Estate Segment Debt and Preferred Equity Segment Total Company Total revenues: Years ended: December 31, 2016 $ 750,233 $ 225,183 $ 975,416 December 31, 2015 721,697 203,536 925,233 December 31, 2014 647,555 199,967 847,522 Income from continuing operations, equity in net gain on sale of interest in unconsolidated joint venture, (loss) gain on sale of real estate, depreciable real estate reserves and loss on early extinguishment of debt Years ended: December 31, 2016 $ 118,199 $ 202,010 $ 320,209 December 31, 2015 96,821 175,800 272,621 December 31, 2014 34,821 170,668 205,489 Total assets As of: December 31, 2016 $ 6,786,479 $ 1,968,134 $ 8,754,613 December 31, 2015 6,791,377 2,041,940 8,833,317 Income from continuing operations represents total revenues less total expenses for the real estate segment and total investment income less allocated interest expense for the debt and preferred equity segment. Interest costs for the debt and preferred equity segment includes actual costs incurred for investments collateralizing the MRA. Interest is imputed on the remaining investments using our 2012 revolving credit facility and corporate borrowing cost. We also allocate loan loss reserves, net of recoveries and transaction related costs to the debt and preferred equity segment. We do not allocate marketing, general and administrative expenses to the debt and preferred equity segment, since we base performance on the individual segments prior to allocating marketing, general and administrative expenses. All other expenses, except interest, relate entirely to the real estate assets. There were no transactions between the above two segments. The table below reconciles income from continuing operations to net income for the years ended December 31, 2016 , 2015 and 2014 (in thousands): Year ended December 31, 2016 2015 2014 Income from continuing operations before equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, depreciable real estate reserves, and loss on early extinguishment of debt. $ 320,209 $ 272,621 $ 205,489 Equity in net gain on sale of interest in unconsolidated joint venture/real estate — — 85,559 (Loss) gain on sale of real estate (6,909 ) 100,190 — Depreciable real estate reserves — (9,998 ) — Loss on early extinguishment of debt — (49 ) (7,385 ) Income from continuing operations 313,300 362,764 283,663 Net income from discontinued operations — — 1,996 Gain on sale of discontinued operations — — 117,579 Net income $ 313,300 $ 362,764 $ 403,238

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2016
Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	Schedule II—Valuation and Qualifying Accounts December 31, 2015 (in thousands) Column A Column B Column C Column D Column E Description Balance at Beginning of Year Additions Charged Against Operations/Recovery Uncollectible Accounts Written-off Balance at End of Year Year Ended December 31, 2016 Tenant and other receivables—allowance $ 5,593 $ 3,604 $ (4,318 ) $ 4,879 Deferred rent receivable—allowance 14,788 3,955 (945 ) 17,798 Year Ended December 31, 2015 Tenant and other receivables—allowance $ 5,820 $ 4,363 $ (4,590 ) $ 5,593 Deferred rent receivable—allowance 17,745 1,775 (4,732 ) 14,788 Year Ended December 31, 2014 Tenant and other receivables—allowance $ 5,382 $ 5,635 $ (5,197 ) $ 5,820 Deferred rent receivable—allowance 18,829 2,916 (4,000 ) 17,745

Schedule III - Real Estate And

Schedule III - Real Estate And Accumulated Depreciation	12 Months Ended
	Dec. 31, 2016
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Schedule III - Real Estate And Accumulated Depreciation	Schedule III—Real Estate And Accumulated Depreciation December 31, 2016 (in thousands) Column A Column B Column C Initial Cost Column D Cost Capitalized Subsequent To Acquisition Column E Gross Amount at Which Carried at Close of Period Column F Column G Column H Column I Description Encumbrances Land Building & Improvements Land Building & Improvements Land Building & Improvements Total Accumulated Depreciation Date of Construction Date Acquired Life on Which Depreciation is Computed 810 Seventh Avenue(1) $ — $ 114,077 $ 476,386 $ — $ 65,985 $ 114,077 $ 542,371 $ 656,448 $ 145,216 1970 1/2007 Various 461 Fifth Avenue(1) — — 62,695 — 10,723 — 73,418 73,418 26,105 1988 10/2003 Various 750 Third Avenue(1) — 51,093 205,972 — 39,436 51,093 245,408 296,501 85,282 1958 7/2004 Various 919 Third Avenue(1)(2) 500,000 223,529 1,033,198 — 38,714 223,529 1,071,912 1,295,441 274,778 1970 1/2007 Various 555 W. 57th Street(1) — 18,846 78,704 — 59,564 18,846 138,268 157,114 58,187 1971 1/1999 Various 1185 Avenue of the Americas(1) — — 728,213 — 39,403 — 767,616 767,616 221,415 1969 1/2007 Various 1350 Avenue of the Americas(1) — 91,038 380,744 — 37,736 91,038 418,480 509,518 114,264 1966 1/2007 Various 1100 King Street—1-6 International Drive(3) — 49,392 104,376 (24,004 ) 23,954 25,388 128,330 153,718 35,062 1983/1986 1/2007 Various 520 White Plains Road(3) — 6,324 26,096 — 6,602 6,324 32,698 39,022 9,158 1979 1/2007 Various 115-117 Stevens Avenue(3) — 5,933 23,826 — 5,390 5,933 29,216 35,149 7,622 1984 1/2007 Various 100 Summit Lake Drive(3) — 10,526 43,109 — 8,476 10,526 51,585 62,111 15,149 1988 1/2007 Various 200 Summit Lake Drive(3) — 11,183 47,906 — 10,448 11,183 58,354 69,537 16,543 1990 1/2007 Various 500 Summit Lake Drive(3) — 9,777 39,048 — 5,290 9,777 44,338 54,115 11,672 1986 1/2007 Various 360 Hamilton Avenue(3) — 29,497 118,250 — 13,844 29,497 132,094 161,591 35,784 2000 1/2007 Various 680 Washington Boulevard(2)(4) — 11,696 45,364 — 10,126 11,696 55,490 67,186 14,462 1989 1/2007 Various 750 Washington Boulevard(2)(4) — 16,916 68,849 — 8,350 16,916 77,199 94,115 19,727 1989 1/2007 Various 1010 Washington Boulevard(4) — 7,747 30,423 — 6,598 7,747 37,021 44,768 9,722 1988 1/2007 Various 1055 Washington Boulevard(4) — 13,516 53,228 — 7,559 13,516 60,787 74,303 15,655 1987 6/2007 Various 400 Summit Lake Drive(3) — 38,889 1 285 2 39,174 3 39,177 — - 1/2007 N/A 609 Fifth Avenue(1) — 36,677 145,954 — 8,270 36,677 154,224 190,901 41,993 1925 6/2006 Various 110 East 42nd Street(1) — 34,000 46,411 — 18,337 34,000 64,748 98,748 15,000 1921 5/2011 Various 304 Park Avenue(1) — 54,189 75,619 300 11,792 54,489 87,411 141,900 13,322 1930 6/2012 Various 635 Sixth Avenue(1) — 24,180 37,158 163 50,189 24,343 87,347 111,690 4,428 1902 9/2012 Various 641 Sixth Avenue(1) — 45,668 67,316 308 3,076 45,976 70,392 116,368 9,339 1902 9/2012 Various 315 West 33rd Street(1) — 195,834 164,429 — 8,919 195,834 173,348 369,182 15,160 2000-2001 11/2013 Various 16 Court Street(7) — 19,217 63,210 — 16,092 19,217 79,302 98,519 10,366 1927-1928 4/2013 Various 125 Chubb Way(5) — 5,884 25,958 — 25,556 5,884 51,514 57,398 9,170 2008 1/2008 Various Williamsburg(6)(7) — 3,677 14,708 2,523 (4,550 ) 6,200 10,158 16,358 1,604 2010 12/2010 Various Column A Column B Column C Initial Cost Column D Cost Capitalized Subsequent To Acquisition Column E Gross Amount at Which Carried at Close of Period Column F Column G Column H Column I Description Encumbrances Land Building & Improvements Land Building & Improvements Land Building & Improvements Total Accumulated Depreciation Date of Construction Date Acquired Life on Which Depreciation is Computed 115 Spring Street(1) — 11,078 44,799 — 1,686 11,078 46,485 57,563 2,918 1900 7/2014 Various 635 Madison Avenue(1) — 205,632 15,805 — — 205,632 15,805 221,437 910 - 9/2014 N/A 125 Park Avenue(1) — 120,900 189,714 — 68,264 120,900 257,978 378,878 54,736 1923 10/2010 Various 625 Madison Ave(1) — — 246,673 — 41,937 — 288,610 288,610 97,690 1956 10/2004 Various 102 Greene Street(1) — 8,215 26,717 35 482 8,250 27,199 35,449 888 1910 11/2014 Various 711 Third Avenue(1)(6)(8) — 19,844 42,499 — 57,916 19,844 100,415 120,259 34,418 1955 5/1998 Various 752 Madison Avenue(1)(6)(9) — 282,415 — 1,871 — 284,286 — 284,286 — 1996/2012 1/2012 N/A 110 Greene Street(1)(10) — 45,120 215,470 — 3,985 45,120 219,455 264,575 9,459 1910 7/2015 Various Other(11) — 1,130 — 78 4,693 1,208 4,693 5,901 18 Various $ 500,000 $ 1,823,639 $ 4,988,828 $ (18,441 ) $ 714,844 $ 1,805,198 $ 5,703,672 $ 7,508,870 $ 1,437,222 __________________________________________________________________ (1) Property located in New York, New York. (2) We own a 51% interest in this property. (3) Property located in Westchester County, New York. (4) Property located in Connecticut. (5) Property located in New Jersey. (6) Property that was transferred in 2015. (7) Property located in Brooklyn, New York. (8) We own a 50% interest in this property. (9) We own a tenancy in common interest in the property. (10) We own a 90% interest in this property. (11) Other includes tenant improvements, capitalized interest and corporate improvements. The changes in real estate for the years ended December 31, 2016 , 2015 and 2014 are as follows (in thousands): 2016 2015 2014 Balance at beginning of year $ 7,428,243 $ 7,203,216 $ 6,670,210 Acquisitions — 329,996 491,023 Improvements 123,173 93,439 102,530 Retirements/disposals (42,546 ) (198,408 ) (60,547 ) Balance at end of year $ 7,508,870 $ 7,428,243 $ 7,203,216 The aggregate cost of land, buildings and improvements, before depreciation, for Federal income tax purposes at December 31, 2016 was approximately $4.9 billion (unaudited). The changes in accumulated depreciation, exclusive of amounts relating to equipment, autos, and furniture and fixtures, for the years ended December 31, 2016 , 2015 and 2014 , are as follows (in thousands): 2016 2015 2014 Balance at beginning of year $ 1,267,598 $ 1,123,412 $ 983,273 Depreciation for year 183,873 175,039 165,840 Retirements/disposals (14,249 ) (30,853 ) (25,701 ) Balance at end of year $ 1,437,222 $ 1,267,598 $ 1,123,412

Significant Accounting Polici29

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include our accounts and those of our subsidiaries, which are wholly-owned or controlled by us. Entities which we do not control through our voting interest and entities which are variable interest entities, but where we are not the primary beneficiary, are accounted for under the equity method. See Note 5, "Debt and Preferred Equity Investments" and Note 6, "Investments in Unconsolidated Joint Ventures." All significant intercompany balances and transactions have been eliminated. We consolidate a variable interest entity, or VIE, in which we are considered the primary beneficiary. The primary beneficiary is the entity that has (i) the power to direct the activities that most significantly impact the entity's economic performance and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could be significant to the VIE. Included in commercial real estate properties on our consolidated balance sheets as of December 31, 2016 and 2015 are $ 1.4 billion and $ 0.3 billion, respectively, related to our consolidated VIEs. Included in mortgages and other loans payable on our consolidated balance sheets as of December 31, 2016 and 2015 are $ 494.1 million and none , respectively, related to our consolidated VIEs. A noncontrolling interest in a consolidated subsidiary is defined as the portion of the equity (net assets) in a subsidiary not attributable, directly or indirectly, to us. Noncontrolling interests are required to be presented as a separate component of equity in the consolidated balance sheet and the presentation of net income is modified to present earnings and other comprehensive income attributed to controlling and noncontrolling interests. We assess the accounting treatment for each joint venture and debt and preferred equity investment. This assessment includes a review of each joint venture or limited liability company agreement to determine the rights provided to each party and whether those rights are protective or participating. For all VIEs, we review such agreements in order to determine which party has the power to direct the activities that most significantly impact the entity's economic performance. In situations where we and our partner approve, among other things, the annual budget, receive a detailed monthly reporting package, meet on a quarterly basis to review the results of the joint venture, review and approve the joint venture's tax return before filing, and approve all leases that cover more than a nominal amount of space relative to the total rentable space at each property, we do not consolidate the joint venture as we consider these to be substantive participation rights that result in shared power of the activities that most significantly impact the performance of the joint venture. Our joint venture agreements typically contain certain protective rights such as requiring partner approval to sell, finance or refinance the property and the payment of capital expenditures and operating expenditures outside of the approved budget or operating plan.
Investment in Commercial Real Estate Properties	Investment in Commercial Real Estate Properties Real estate properties are presented at cost less accumulated depreciation and amortization. Costs directly related to the development or redevelopment of properties are capitalized. Ordinary repairs and maintenance are expensed as incurred; major replacements and betterments, which improve or extend the life of the asset, are capitalized and depreciated over their estimated useful lives. A property to be disposed of is reported at the lower of its carrying value or its estimated fair value, less its cost to sell. Once an asset is held for sale, depreciation expense is no longer recorded. The Company adopted ASU 2014-08 effective January 1, 2015 which raised the threshold for disposals to qualify as discontinued operations to include only dispositions that represent a strategic shift in an entity’s operations. The guidance was applied prospectively for new disposals. No properties were held for sale during 2016. The Company classified 140 Grand Street in White Plains, New York as held for sale as of September 30, 2015 and 131-137 Spring Street as of June 30, 2015 and included the results of operations in continuing operations for all periods presented. Discontinued operations included the results of operations of real estate assets sold or held for sale prior to January 1, 2015. This included 673 First Avenue, which was sold during 2014. See Note 4, "Properties Held for Sale and Dispositions." Properties are depreciated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives are as follows: Category Term Building (fee ownership) 40 years Building improvements shorter of remaining life of the building or useful life Building (leasehold interest) lesser of 40 years or remaining term of the lease Property under capital lease remaining lease term Furniture and fixtures four to seven years Tenant improvements shorter of remaining term of the lease or useful life Depreciation expense (including amortization of capital lease assets) totaled $196.2 million , $187.2 million , and $184.3 million and for the years ended December 31, 2016 , 2015 and 2014 , respectively. On a periodic basis, we assess whether there are any indications that the value of our real estate properties may be other than temporarily impaired or that their carrying value may not be recoverable. A property's value is considered impaired if management's estimate of the aggregate future cash flows (undiscounted) to be generated by the property is less than the carrying value of the property. To the extent impairment has occurred, the loss will be measured as the excess of the carrying amount of the property over the calculated fair value of the property. We also evaluate our real estate properties for potential impairment when a real estate property has been classified as held for sale. Real estate assets held for sale are valued at the lower of either their carrying value or fair value less costs to sell. We do not believe that there were any indicators of impairment at any of our consolidated properties at December 31, 2016 . During the third quarter of 2015, we recorded a $10.0 million charge in connection with the expected sale of one of our properties, which closed in the fourth quarter of 2015. This charge is included in depreciable real estate reserves in the consolidated statements of operations. We incur a variety of costs in the development and leasing of our properties. After determination is made to capitalize a cost, it is allocated to the specific component of a project that is benefited. Determination of when a development project is substantially complete and capitalization must cease involves a degree of judgment. The costs of land and building under development include specifically identifiable costs. The capitalized costs include, but are not limited to, pre-construction costs essential to the development of the property, development costs, construction costs, interest costs, real estate taxes, salaries and related costs and other costs incurred during the period of development. We consider a construction project as substantially completed and held available for occupancy upon the completion of tenant improvements, but no later than one year after major construction activity ceases. We cease capitalization on the portions substantially completed and occupied or held available for occupancy, and capitalize only those costs associated with the portions under construction. Results of operations of properties acquired are included in the consolidated statements of operations from the date of acquisition. We recognize the assets acquired, liabilities assumed (including contingencies) and any noncontrolling interests in an acquired entity at their fair values on the acquisition date. We expense transaction costs related to the acquisition of certain assets as incurred, which are included in transaction related costs on our consolidated statements of operations. In January, 2017, the FASB published ASU No. 2017-01, Business Combinations: Clarifying the Definition of a Business, which provides guidance as to whether transaction costs should be expensed or capitalized. Refer to Note 2, Accounting Standards Updates for the Company's adoption of the new guidance. When we acquire our partner's equity interest in an existing unconsolidated joint venture and gain control over the investment, we record the consolidated investment at fair value. The difference between the book value of our equity investment on the purchase date and our share of the fair value of the investment's purchase price is recorded as a purchase price fair value adjustment in our consolidated statements of operations. We allocate the purchase price of real estate to land and building (inclusive of tenant improvements) and, if determined to be material, intangibles, such as the value of above- and below-market leases and origination costs associated with the in-place leases. We depreciate the amount allocated to building (inclusive of tenant improvements) over their estimated useful lives, which generally range from three to 40 years . We amortize the amount allocated to the above- and below-market leases over the remaining term of the associated lease, which generally range from one to 14 years , and record it as either an increase (in the case of below-market leases) or a decrease (in the case of above-market leases) to rental income. We amortize the amount allocated to the values associated with in-place leases over the expected term of the associated lease, which generally ranges from one to 14 years . If a tenant vacates its space prior to the contractual termination of the lease and no rental payments are being made on the lease, any unamortized balance of the related intangible will be written off. The tenant improvements and origination costs are amortized as an expense over the remaining life of the lease (or charged against earnings if the lease is terminated prior to its contractual expiration date). We assess fair value of the leases based on estimated cash flow projections that utilize appropriate discount and capitalization rates and available market information. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. To the extent acquired leases contain fixed rate renewal options that are below-market and determined to be material, we amortize such below-market lease value into rental income over the renewal period.
Cash and Cash Equivalents	Cash and Cash Equivalents We consider all highly liquid investments with maturity of three months or less when purchased to be cash equivalents.
Restricted Cash	Restricted Cash Restricted cash primarily consists of security deposits held on behalf of our tenants, interest reserves, as well as capital improvement and real estate tax escrows required under certain loan agreements.
Investment in Unconsolidated Joint Ventures	Investment in Unconsolidated Joint Ventures We account for our investments in unconsolidated joint ventures under the equity method of accounting in cases where we exercise significant influence over, but do not control, these entities and are not considered to be the primary beneficiary. We consolidate those joint ventures that we control or which are VIEs and where we are considered to be the primary beneficiary. In all these joint ventures, the rights of the joint venture partner are both protective as well as participating. Unless we are determined to be the primary beneficiary in a VIE, these participating rights preclude us from consolidating these VIE entities. These investments are recorded initially at cost, as investments in unconsolidated joint ventures, and subsequently adjusted for equity in net income (loss) and cash contributions and distributions. Equity in net income (loss) from unconsolidated joint ventures is allocated based on our ownership or economic interest in each joint venture. When a capital event (as defined in each joint venture agreement) such as a refinancing occurs, if return thresholds are met, future equity income will be allocated at our increased economic interest. We recognize incentive income from unconsolidated real estate joint ventures as income to the extent it is earned and not subject to a clawback feature. Distributions we receive from unconsolidated real estate joint ventures in excess of our basis in the investment are recorded as offsets to our investment balance if we remain liable for future obligations of the joint venture or may otherwise be committed to provide future additional financial support. None of the joint venture debt is recourse to us. See Note 6, "Investments in Unconsolidated Joint Ventures." We assess our investments in unconsolidated joint ventures for recoverability, and if it is determined that a loss in value of the investment is other than temporary, we write down the investment to its fair value. We evaluate our equity investments for impairment based on the joint ventures' projected discounted cash flows. We do not believe that the values of any of our equity investments were impaired at December 31, 2016 . We may originate loans for real estate acquisition, development and construction, where we expect to receive some of the residual profit from such projects. When the risk and rewards of these arrangements are essentially the same as an investor or joint venture partner, we account for these arrangements as real estate investments under the equity method of accounting for investments. Otherwise, we account for these arrangements consistent with our loan accounting for our debt and preferred equity investments.
Deferred Lease Costs	Deferred Lease Costs Deferred lease costs consist of fees and direct costs incurred to initiate and renew operating leases and are amortized on a straight-line basis over the related lease term.
Deferred Financing Costs	Deferred Financing Costs Deferred financing costs represent commitment fees, legal, title and other third party costs associated with obtaining commitments for financing which result in a closing of such financing. These costs are amortized over the terms of the respective agreements. Unamortized deferred financing costs are expensed when the associated debt is refinanced or repaid before maturity. Costs incurred in seeking financing transactions, which do not close, are expensed in the period in which it is determined that the financing will not close. Deferred debt issuance costs related to a recognized debt liability are presented in the balance sheet as a direct deduction from the carrying amount of that debt liability.
Revenue Recognition	Revenue Recognition Rental revenue is recognized on a straight-line basis over the term of the lease. Rental revenue recognition commences when the tenant takes possession or controls the physical use of the leased space. In order for the tenant to take possession, the leased space must be substantially ready for its intended use. To determine whether the leased space is substantially ready for its intended use, management evaluates whether we are or the tenant is the owner of tenant improvements for accounting purposes. When management concludes that we are the owner of tenant improvements, rental revenue recognition begins when the tenant takes possession of the finished space, which is when such tenant improvements are substantially complete. In certain instances, when management concludes that we are not the owner (the tenant is the owner) of tenant improvements, rental revenue recognition begins when the tenant takes possession of or controls the space. When management concludes that we are the owner of tenant improvements for accounting purposes, we record amounts funded to construct the tenant improvements as a capital asset. For these tenant improvements, we record amounts reimbursed by tenants as a reduction of the capital asset. When management concludes that the tenant is the owner of tenant improvements for accounting purposes, we record our contribution towards those improvements as a lease incentive, which is included in deferred costs, net on our consolidated balance sheets and amortized as a reduction to rental revenue on a straight-line basis over the term of the lease. The excess of rents recognized over amounts contractually due pursuant to the underlying leases are included in deferred rents receivable on the consolidated balance sheets. We establish, on a current basis, an allowance for future potential tenant credit losses, which may occur against this account. The balance reflected on the consolidated balance sheets is net of such allowance. In addition to base rent, our tenants also generally will pay their pro rata share of increases in real estate taxes and operating expenses for the building over a base year. In some leases, in lieu of paying additional rent based upon increases in building operating expenses, the tenant will pay additional rent based upon increases in the wage rate paid to porters over the porters' wage rate in effect during a base year or increases in the consumer price index over the index value in effect during a base year. In addition, many of our leases contain fixed percentage increases over the base rent to cover escalations. Electricity is most often supplied by the landlord either on a sub-metered basis, or rent inclusion basis (i.e., a fixed fee is included in the rent for electricity, which amount may increase based upon increases in electricity rates or increases in electrical usage by the tenant). Base building services other than electricity (such as heat, air conditioning and freight elevator service during business hours, and base building cleaning) are typically provided at no additional cost, with the tenant paying additional rent only for services which exceed base building services or for services which are provided outside normal business hours. These escalations are based on actual expenses incurred in the prior calendar year. If the expenses in the current year are different from those in the prior year, then during the current year, the escalations will be adjusted to reflect the actual expenses for the current year. We record a gain on sale of real estate when title is conveyed to the buyer, subject to the buyer's financial commitment being sufficient to provide economic substance to the sale and provided that we have no substantial economic involvement with the buyer. Interest income on debt and preferred equity investments is accrued based on the contractual terms of the instruments and when, in the opinion of management, it is deemed collectible. Some debt and preferred equity investments provide for accrual of interest at specified rates, which differ from current payment terms. Interest is recognized on such loans at the accrual rate subject to management's determination that accrued interest is ultimately collectible, based on the underlying collateral and operations of the borrower. If management cannot make this determination, interest income above the current pay rate is recognized only upon actual receipt. Deferred origination fees, original issue discounts and loan origination costs, if any, are recognized as an adjustment to the interest income over the terms of the related investments using the effective interest method. Fees received in connection with loan commitments are also deferred until the loan is funded and are then recognized over the term of the loan as an adjustment to yield. Discounts or premiums associated with the purchase of loans are amortized or accreted into interest income as a yield adjustment on the effective interest method based on expected cash flows through the expected maturity date of the related investment. If we purchase a debt or preferred equity investment at a discount, intend to hold it until maturity and expect to recover the full value of the investment, we accrete the discount into income as an adjustment to yield over the term of the investment. If we purchase a debt or preferred equity investment at a discount with the intention of foreclosing on the collateral, we do not accrete the discount. For debt investments acquired at a discount for credit quality, the difference between contractual cash flows and expected cash flows at acquisition is not accreted. Anticipated exit fees, the collection of which is expected, are also recognized over the term of the loan as an adjustment to yield. Debt and preferred equity investments are placed on a non-accrual status at the earlier of the date at which payments become 90 days past due or when, in the opinion of management, a full recovery of interest income becomes doubtful. Interest income recognition on any non-accrual debt or preferred equity investment is resumed when such non-accrual debt or preferred equity investment becomes contractually current and performance is demonstrated to be resumed. Interest is recorded as income on impaired loans only to the extent cash is received. We may syndicate a portion of the loans that we originate or sell the loans individually. When a transaction meets the criteria for sale accounting, we derecognize the loan sold and recognize gain or loss based on the difference between the sales price and the carrying value of the loan sold. Any related unamortized deferred origination fees, original issue discounts, loan origination costs, discounts or premiums at the time of sale are recognized as an adjustment to the gain or loss on sale, which is included in investment income on the consolidated statement of operations. Any fees received at the time of sale or syndication are recognized as part of investment income. Asset management fees are recognized on a straight-line basis over the term of the asset management agreement.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts We maintain an allowance for doubtful accounts for estimated losses resulting from the inability of our tenants to make required payments. If the financial condition of a specific tenant were to deteriorate, resulting in an impairment of its ability to make payments, additional allowances may be required.
Reserve for Possible Credit Losses	Reserve for Possible Credit Losses The expense for possible credit losses in connection with debt and preferred equity investments is the charge to earnings to increase the allowance for possible credit losses to the level that we estimate to be adequate, based on Level 3 data, considering delinquencies, loss experience and collateral quality. Other factors considered include geographic trends, product diversification, the size of the portfolio and current economic conditions. Based upon these factors, we establish a provision for possible credit loss on each individual investment. When it is probable that we will be unable to collect all amounts contractually due, the investment is considered impaired. Where impairment is indicated on an investment that is held to maturity, a valuation allowance is measured based upon the excess of the recorded investment amount over the net fair value of the collateral. Any deficiency between the carrying amount of an asset and the calculated value of the collateral is charged to expense. We continue to assess or adjust our estimates based on circumstances of a loan and the underlying collateral. If additional information reflects increased recovery of our investment, we will adjust our reserves accordingly. There were no loan reserves recorded during years ended December 31, 2016 , 2015 , and 2014 . Debt and preferred equity investments held for sale are carried at the lower of cost or fair market value using available market information obtained through consultation with dealers or other originators of such investments as well as discounted cash flow models based on Level 3 data pursuant to ASC 820-10. As circumstances change, management may conclude not to sell an investment designated as held for sale. In such situations, the investment will be reclassified at its net carrying value to debt and preferred equity investments held to maturity. For these reclassified investments, the difference between the current carrying value and the expected cash to be collected at maturity will be accreted into income over the remaining term of the investment.
Rent Expense	Rent Expense Rent expense is recognized on a straight-line basis over the initial term of the lease. The excess of the rent expense recognized over the amounts contractually due pursuant to the underlying lease is included in the deferred lease payable on the consolidated balance sheets.
Exchangeable Debt Instruments	Exchangeable Debt Instruments The initial proceeds from exchangeable debt that may be settled in cash, including partial cash settlements, are bifurcated between a liability component and an equity component associated with the embedded conversion option. The objective of the accounting guidance is to require the liability and equity components of exchangeable debt to be separately accounted for in a manner such that the interest expense on the exchangeable debt is not recorded at the stated rate of interest but rather at an effective rate that reflects the issuer's conventional debt borrowing rate at the date of issuance. We calculate the liability component of exchangeable debt based on the present value of the contractual cash flows discounted at our comparable market conventional debt borrowing rate at the date of issuance. The difference between the principal amount and the fair value of the liability component is reported as a discount on the exchangeable debt that is accreted as additional interest expense from the issuance date through the contractual maturity date using the effective interest method. A portion of this additional interest expense may be capitalized to the development and redevelopment balances qualifying for interest capitalization each period. The liability component of the exchangeable debt is reported net of discounts on our consolidated balance sheets. We calculate the equity component of exchangeable debt based on the difference between the initial proceeds received from the issuance of the exchangeable debt and the fair value of the liability component at the issuance date. The equity component is included in additional paid-in-capital, net of issuance costs, on our consolidated balance sheets. We allocate issuance costs for exchangeable debt between the liability and the equity components based on their relative values.
Income Taxes	Income Taxes SL Green is taxed as a REIT under Section 856(c) of the Code. As a REIT, SL Green generally is not subject to Federal income tax. To maintain its qualification as a REIT, SL Green must distribute at least 90% of its REIT taxable income to its stockholders and meet certain other requirements. If SL Green fails to qualify as a REIT in any taxable year, SL Green will be subject to Federal income tax on SL Green's taxable income at regular corporate rates. SL Green may also be subject to certain state, local and franchise taxes. Under certain circumstances, Federal income and excise taxes may be due on SL Green's undistributed taxable income. ROP is a disregarded entity of SL Green Operating Partnership, L.P. for federal income tax purposes, and, as a result, all income and losses of ROP are considered income and losses of SL Green Operating Partnership, L. P. No provision has been made for income taxes in the consolidated financial statements since such taxes, if any, are the responsibility of the individual partners of SL Green Operating Partnership, L.P. We follow a two-step approach for evaluating uncertain tax positions. Recognition (step one) occurs when an enterprise concludes that a tax position, based solely on its technical merits, is more-likely-than-not to be sustained upon examination. Measurement (step two) determines the amount of benefit that is more-likely-than-not to be realized upon settlement. Derecognition of a tax position that was previously recognized would occur when a company subsequently determines that a tax position no longer meets the more-likely-than-not threshold of being sustained. The use of a valuation allowance as a substitute for derecognition of tax positions is prohibited.
Derivative Instruments	Derivative Instruments In the normal course of business, we use a variety of commonly used derivative instruments, such as interest rate swaps, caps, collars and floors, to manage, or hedge, interest rate risk. Effectiveness is essential for those derivatives that we intend to qualify for hedge accounting. Some derivative instruments are associated with an anticipated transaction. In those cases, hedge effectiveness criteria also require that it be probable that the underlying transaction occurs. Instruments that meet these hedging criteria are formally designated as hedges at the inception of the derivative contract. To determine the fair values of derivative instruments, we use a variety of methods and assumptions that are based on market conditions and risks existing at each balance sheet date. For the majority of financial instruments including most derivatives, long-term investments and long-term debt, standard market conventions and techniques such as discounted cash flow analysis, option pricing models, replacement cost, and termination cost are used to determine fair value. All methods of assessing fair value result in a general approximation of value, and such value may never actually be realized. In the normal course of business, we are exposed to the effect of interest rate changes and limit these risks by following established risk management policies and procedures including the use of derivatives. To address exposure to interest rates, derivatives are used primarily to fix the rate on debt based on floating-rate indices and manage the cost of borrowing obligations. We use a variety of commonly used derivative products that are considered plain vanilla derivatives. These derivatives typically include interest rate swaps, caps, collars and floors. We expressly prohibit the use of unconventional derivative instruments and using derivative instruments for trading or speculative purposes. Further, we have a policy of only entering into contracts with major financial institutions based upon their credit ratings and other factors. We may employ swaps, forwards or purchased options to hedge qualifying forecasted transactions. Gains and losses related to these transactions are deferred and recognized in net income as interest expense in the same period or periods that the underlying transaction occurs, expires or is otherwise terminated. Hedges that are reported at fair value and presented on the balance sheet could be characterized as cash flow hedges or fair value hedges. Interest rate caps and collars are examples of cash flow hedges. Cash flow hedges address the risk associated with future cash flows of interest payments. For all hedges held by us and which were deemed to be fully effective in meeting the hedging objectives established by our corporate policy governing interest rate risk management, no net gains or losses were reported in earnings. The changes in fair value of hedge instruments are reflected in accumulated other comprehensive income. For derivative instruments not designated as hedging instruments, the gain or loss, resulting from the change in the estimated fair value of the derivative instruments, is recognized in current earnings during the period of change.
Shares Contributed by Parent Company	Shares Contributed by Parent Company We present shares of SL Green common stock as a contra-equity account in our financial statements.
Use of Estimates	Use of Estimates 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.
Concentrations of Credit Risk	Concentrations of Credit Risk 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 in excess of insured amounts with high quality financial institutions. The collateral securing our debt and preferred equity investments is located in New York City. See Note 5, "Debt and Preferred Equity Investments." We perform ongoing credit evaluations of our tenants and require most tenants to provide security deposits or letters of credit. Though these security deposits and letters of credit are insufficient to meet the total value of a tenant's lease obligation, they are a measure of good faith and a source of funds to offset the economic costs associated with lost revenue and the costs associated with re-tenanting a space. The properties in our real estate portfolio are primarily located in Manhattan, we also have properties located in Brooklyn, Westchester County, Connecticut and New Jersey. The tenants located in our buildings operate in various industries.
Reclassification	Reclassification Certain prior year balances have been reclassified to conform to our current year presentation
Accounting Standards Updates	Accounting Standards Updates In January, 2017, the FASB issued Accounting Standards Update (ASU) No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business The guidance clarifies the definition of a business and provides guidance to assist with determining whether transactions should be accounted for as acquisitions of assets or businesses. The main provision is that an acquiree is not a business if substantially all of the fair value of the gross assets is concentrated in a single identifiable asset or group of assets. The Company adopted the guidance on the issuance date effective January 5, 2017. The Company expects that most of our real estate acquisitions will be considered asset acquisitions under the new guidance and that transaction costs will be capitalized to the investment basis which is then subject to a purchase price allocation based on relative fair value. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. The ASU provides final guidance on eight cash flow issues, including debt prepayment or debt extinguishment costs, contingent consideration payments made after a business combination, distributions received from equity method investees, separately identifiable cash flows and application of the predominance principle, and others. The amendments in the ASU are effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The Company has not yet adopted this new guidance and is currently evaluating the impact of adopting this new accounting standard on the Company’s consolidated financial statements. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The guidance changes how entities will measure credit losses for most financial assets and certain other instruments that aren’t measured at fair value through net income. The guidance replaces the current ‘incurred loss’ model with an ‘expected loss’ approach. The guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted after December 2018. The Company has not yet adopted this new guidance and is currently evaluating the impact of adopting this new accounting standard on the Company’s consolidated financial statements. In March 2016, the FASB issued ASU 2016-07, Investments Equity Method and Joint Ventures (Topic 323). The guidance eliminates the requirement that an entity retroactively adopt the equity method of accounting if an investment qualifies for use of the equity method as a result of an increase in the level of ownership or degree of influence. The amendments require that the equity method investor add the cost of acquiring the additional interest in the investee to the current basis of the investor’s previously held interest and adopt the equity method of accounting as of the date the investment becomes qualified for equity method accounting. The Company adopted the guidance effective January 1, 2017 and there is no impact on the Company’s consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases. The guidance requires lessees to recognize lease assets and lease liabilities for those leases classified as operating leases under the previous standard. Depending on the lease classification, lessees will recognize expense based on the effective interest method for finance leases or on a straight-line basis for operating leases. The accounting applied by a lessor is largely unchanged from that applied under the previous standard. One of the impacts on the Company will be the presentation and disclosure in the financial statements of non-lease components such as charges to tenants for a building’s operating expenses. The non-lease components will be presented separately from the lease components in both the Consolidated Statements of Operations and Consolidated Balance Sheets. Another impact is the measurement and presentation of ground leases under which the Company is lessee. The Company is required to record a liability for the obligation to make payments under the lease and an asset for the right to use the underlying asset during the lease term and will also apply the new expense recognition requirements given the lease classification. The Company is currently quantifying these impacts. The guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. The Company anticipates adopting this guidance January 1, 2019 and will apply the modified retrospective approach. In January 2016, the FASB issued ASU 2016-01 (ASU 825-10), Recognition and Measurement of Financial Assets and Financial Liabilities. The guidance requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and to record changes in instruments-specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. The guidance is effective for fiscal years beginning after December 15, 2017, and for interim periods therein. The Company has not yet adopted this new guidance and is currently evaluating the impact of adopting this new accounting standard on the Company’s consolidated financial statements. In April 2015, the FASB issued final guidance to simplify the presentation of debt issuance costs by requiring debt issuance costs to be presented as a deduction from the corresponding debt liability (ASU 2015-03). The guidance requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability. The Company adopted the guidance effective January 1, 2016. Accordingly, as of December 31, 2016 and 2015 , $22.8 million and $25.2 million , respectively, of deferred debt issuance cost, net of amortization are presented as a direct reduction within Mortgages and other loans payable, Revolving credit facility, Term loan and senior unsecured notes on the Company's consolidated balance sheets. In February 2015, the FASB issued guidance that amends the current consolidation guidance, including introducing a separate consolidation analysis specific to limited partnerships and other similar entities (ASU 2015-02). Under this analysis, limited partnerships and other similar entities will be considered a VIE unless the limited partners hold substantive kick-out rights or participating rights. The Company adopted the guidance effective January 1, 2016. Under the revised guidance, certain entities, including the Operating Partnership, now qualify as variable interest entities while some of our entities originally classified as variable interest entities no longer meet the criteria. The change in designation did not have a material impact on our consolidated financial statements and did not change the consolidation conclusion on these entities. In May 2014, the FASB issued a new comprehensive revenue recognition guidance which requires us to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which we expect to be entitled in exchange for those goods and services (ASU 2014-09). The guidance also requires enhanced disclosures to help users of financial statements better understand the nature, amount, timing, and uncertainty of revenue that is recognized. In March 2016, the FASB issued implementation guidance which clarifies principal versus agent considerations in reporting revenue gross versus net (ASU 2016-08). In April 2016, the FASB issued implementation guidance which clarifies the identification of performance obligations (ASU 2016-10). In April 2016, the FASB amended its new revenue recognition guidance on identifying performance obligations to allow entities to disregard items that are immaterial and clarify when a good or service is separately identifiable (ASU 2016-10). In May 2016, the FASB issued implementation guidance relating to transition, collectability, noncash consideration and presentation matters (ASU 2016-12). These ASUs are effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted but not before interim and annual reporting periods beginning after December 15, 2016. The new guidance can be applied either retrospectively to each prior reporting period presented, or as a cumulative-effect adjustment as of the date of adoption. The Company anticipates adopting this guidance January 1, 2018, and applying the cumulative-effect adoption method. Since the Company’s revenue is related to leasing activities, the adoption of this guidance will not have a material impact on the consolidated financial statements.
Fair Value Measurements	Fair Value Measurements We are required to disclose fair value information with regard to our financial instruments, whether or not recognized in the consolidated balance sheets, for which it is practical to estimate fair value. The FASB guidance defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. We measure and/or disclose the estimated fair value of financial assets and liabilities based on a hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity and the reporting entity’s own assumptions about market participant assumptions. This hierarchy consists of three broad levels: Level 1 - quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity can access at the measurement date; Level 2 - inputs other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly; and Level 3 - unobservable inputs for the asset or liability that are used when little or no market data is available. We follow this hierarchy for our assets and liabilities measured at fair value on a recurring and nonrecurring basis. In instances in which the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level of input that is significant to the fair value measurement in its entirety. Our assessment of the significance of the particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. We determine other than temporary impairment in real estate investments and debt and preferred equity investments, including intangibles utilizing cash flow projections that apply, among other things, estimated revenue and expense growth rates, discount rates and capitalization rates, which are classified as Level 3 inputs. The fair value of derivative instruments is based on current market data received from financial sources that trade such instruments and are based on prevailing market data and derived from third party proprietary models based on well-recognized financial principles and reasonable estimates about relevant future market conditions, which are classified as Level 2 inputs. The financial assets and liabilities that are not measured at fair value on our consolidated balance sheets include cash and cash equivalents, restricted cash, accounts receivable, accounts payable and accrued expenses, debt and preferred equity investments, mortgages and other loans payable and other secured and unsecured debt. The carrying amount of cash and cash equivalents, restricted cash, accounts receivable, and accounts payable and accrued expenses reported in our consolidated balance sheets approximates fair value due to the short term nature of these instruments. The fair value of debt and preferred equity investments, which is classified as Level 3, is estimated by discounting the future cash flows using current interest rates at which similar loans with the same maturities would be made to borrowers with similar credit ratings. The fair value of borrowings, which is classified as Level 3, is estimated by discounting the contractual cash flows of each debt instrument to their present value using adjusted market interest rates, which is provided by a third-party specialist.

Organization and Basis of Pre30

Organization and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of commercial office properties	As of December 31, 2016 , we owned the following interests in properties in the New York Metropolitan area, primarily in midtown Manhattan. Our investments in the New York Metropolitan area also include investments in Brooklyn, Westchester County, Connecticut and New Jersey, which are collectively known as the Suburban properties: Location Type Number of Properties Approximate Square Feet (unaudited) Weighted Average (1) (unaudited) Commercial: Manhattan Office 16 8,463,245 96.4 % Retail (2)(3) 5 352,892 97.6 % Fee Interest 2 197,654 100.0 % 23 9,013,791 96.5 % Suburban Office 18 3,251,000 83.2 % Retail 1 52,000 100.0 % 19 3,303,000 83.4 % Total commercial properties 42 12,316,791 93.0 % Residential: Manhattan Residential (2) — 222,855 93.1 % Total portfolio 42 12,539,646 93.0 % ____________________________________________________________________ (1) The weighted average occupancy for commercial properties represents the total occupied square feet divided by total square footage at acquisition. The weighted average occupancy for residential properties represents the total occupied units divided by total available units. (2) As of December 31, 2016 we owned a building that was comprised of approximately 270,132 square feet (unaudited) of retail space and approximately 222,855 square feet (unaudited) of residential space. For the purpose of this report, we have included the building in the number of retail properties we own. However, we have included only the retail square footage in the retail approximate square footage, and have listed the balance of the square footage as residential square footage. (3) Includes two unconsolidated joint venture retail properties at 131-137 Spring Street comprised of approximately 68,342 square feet (unaudited).

Significant Accounting Polici31

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Schedule of estimated useful lives	The estimated useful lives are as follows: Category Term Building (fee ownership) 40 years Building improvements shorter of remaining life of the building or useful life Building (leasehold interest) lesser of 40 years or remaining term of the lease Property under capital lease remaining lease term Furniture and fixtures four to seven years Tenant improvements shorter of remaining term of the lease or useful life
Summary of identified intangible assets (acquired above-market leases and in-place leases) and intangible liabilities (acquired below-market leases)	The following summarizes our identified intangible assets (acquired above-market leases and in-place leases) and intangible liabilities (acquired below-market leases) as of December 31, 2016 and 2015 (in thousands): December 31, 2016 December 31, 2015 Identified intangible assets (included in other assets): Gross amount $ 311,830 $ 307,824 Accumulated amortization (253,064 ) (235,040 ) Net (1) $ 58,766 $ 72,784 Identified intangible liabilities (included in deferred revenue): Gross amount $ 524,793 $ 523,228 Accumulated amortization (368,738 ) (346,857 ) Net (1) $ 156,055 $ 176,371 ____________________________________________________________________ (1) As of December 31, 2016, no net intangible assets and no net intangible liabilities were reclassified to assets held for sale and liabilities related to assets held for sale.
Schedule of estimated annual amortization of acquired below-market leases, net of acquired above-market leases	The estimated annual amortization of acquired above-market leases, net of acquired (below-market) leases (a component of rental revenue), for each of the five succeeding years is as follows (in thousands): 2017 $ (15,745 ) 2018 (13,628 ) 2019 (13,135 ) 2020 (12,342 ) 2021 (3,831 )
Schedule of estimated annual amortization of all other identifiable assets	The estimated annual amortization of all other identifiable assets (a component of depreciation and amortization expense) including tenant improvements for each of the five succeeding years is as follows (in thousands): 2017 $ 14,403 2018 9,195 2019 7,519 2020 6,617 2021 3,719

Property Acquisition (Tables)

Property Acquisition (Tables)	12 Months Ended
	Dec. 31, 2016
2015 Acquisitions
Business Acquisition [Line Items]
Schedule of recognized identified assets acquired and liabilities assumed	During the year ended December 31, 2016, we finalized the purchase price allocations for the following 2015 acquisition based on facts and circumstances that existed at the acquisition date for the property (in thousands): 110 Greene Street (1)(2) Acquisition Date July 2015 Ownership Type Fee Interest Property Type Office Purchase Price Allocation: Land $ 45,120 Building and building leasehold 215,470 Above-market lease value — Acquired in-place leases 8,967 Other assets, net of other liabilities — Assets acquired 269,557 Mark-to-market assumed debt — Below-market lease value (14,557 ) Derivatives — Liabilities assumed (14,557 ) Purchase price $ 255,000 Net consideration funded by us at closing, excluding consideration financed by debt $ 255,000 Equity and/or debt investment held $ — Debt assumed $ — __________________________________________________________ (1) Based on our preliminary analysis of the purchase price, we had allocated $89.3 million and $165.8 million to land and building, respectively, at 110 Greene Street. The impact to our consolidated statements of operations for the twelve months ended December 31, 2016 was an increase in rental revenue of $1.6 million for the amortization of aggregate below-market leases and an additional $3.1 million of depreciation expense. (2) We acquired a 90.0% controlling interest in this property for consideration that included the issuance of $5.0 million and $6.7 million aggregate liquidation preferences of Series P and Q Preferred Units, respectively, of limited partnership interest of the Operating Partnership and cash.
2014 Acquisitions
Business Acquisition [Line Items]
Schedule of recognized identified assets acquired and liabilities assumed	During the year ended December 31, 2015, we finalized the purchase price allocation based on third party appraisal and additional facts and circumstances that existed at the acquisition dates for the following 2014 acquisitions (in thousands): 102 Greene (1) 635 Madison Ave (1) 115 Spring Street (1) Acquisition Date October 2014 September 2014 July 2014 Ownership Type Fee Interest Fee Interest Fee Interest Property Type Retail Land Retail Purchase Price Allocation: Land $ 8,215 $ 205,632 $ 11,078 Building and building leasehold 26,717 15,805 44,799 Above-market lease value — — — Acquired in-place lease value 1,015 17,345 2,037 Other assets, net of other liabilities 3 — — Assets acquired 35,950 238,782 57,914 Mark-to-market assumed debt — — — Below-market lease value 3,701 85,036 4,789 Liabilities assumed 3,701 85,036 4,789 Purchase price $ 32,249 $ 153,746 $ 53,125 Net consideration funded by us at closing, excluding consideration financed by debt $ 32,249 $ 153,746 $ 53,125 Equity and/or debt investment held $ — $ — $ — Debt assumed $ — $ — $ — ____________________________________________________________________ (1) Based on our preliminary analysis of the purchase price, we had allocated $11.3 million and $21.0 million to land and building, respectively, at 102 Greene Street, $153.7 million to land at 635 Madison Avenue, and $15.9 million and $37.2 million to land and building, respectively, at 115 Spring Street. The impact to our consolidated statement of operations for the year ended December 31, 2015 was $1.9 million in rental revenue for the amortization of aggregate below-market leases and $1.1 million of depreciation expense.

Property Held for Sale and Di33

Property Held for Sale and Dispositions (Tables)	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of properties sold and income from discontinued operations	The following table summarizes net income from discontinued operations for the years ended December 31, 2016 , 2015 , and 2014 (in thousands): Year Ended December 31, 2016 2015 2014 Revenues Rental revenue $ — $ — $ 7,853 Escalation and reimbursement revenues — — 1,080 Other income — — — Total revenues — — 8,933 Operating expenses — — 1,222 Real estate taxes — — 1,402 Ground rent — — 3,001 Interest expense, net of interest income — — 879 Depreciation and amortization — — 433 Total expenses — — 6,937 Net income from discontinued operations $ — $ — $ 1,996 The following table summarizes the properties sold during the years ended December 31, 2016 , 2015 and 2014 : Property Disposition Date Property Type Approximate Usable Square Feet (unaudited) Sale Price (1) (in millions) Gain (loss) on Sale (2) (in millions) 7 International Drive May 2016 Land 31 Acres $ 20.0 $ (6.9 ) 140 Grand Street (3) December 2015 Office 130,100 $ 22.4 $ (10.5 ) 131-137 Spring Street (4) August 2015 Office 68,342 $ 277.8 $ 101.1 673 First Avenue May 2014 Office 422,000 $ 145.0 $ 117.6 ____________________________________________________________________ (1) Sales price represents the actual sales price for the property or the gross asset valuation for the interest in a property. (2) The gain on sale for 131-137 Spring Street and 673 First Avenue are net of $4.1 million and $3.4 million , respectively, in employee compensation awards accrued in connection with the realization of these investment gains as a bonus to certain employees that were instrumental in realizing the gain on sale. Additionally, amounts do not include adjustments for expenses recorded in subsequent periods. (3) Gain/(loss) on sale includes a $10.0 million charge that was recorded during the third quarter of 2015. This charge is included in depreciable real estate reserves in the consolidated statement of operations. (4) We sold an 80% interest in 131-137 Spring Street and have subsequently accounted for our interest in the properties as an investment in unconsolidated joint ventures. See Note 5, "Debt, Preferred Equity and Other Investments."

Debt and Preferred Equity Inv34

Debt and Preferred Equity Investments (Tables)	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Schedule of debt investments	As of December 31, 2016 and 2015 , we held the following debt investments with an aggregate weighted average current yield of 9.34% at December 31, 2016 (in thousands): Loan Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 Carrying Value (1) Maturity Date (2) Fixed Rate Investments: Jr. Mortgage Participation/Mezzanine Loan (3) $ — $ 1,109,000 $ 193,422 $ 104,661 March 2017 Mezzanine Loan (4a) — 502,100 66,129 41,115 June 2017 Mortgage Loan (5) — — 26,311 26,262 February 2019 Mortgage Loan — — 380 513 August 2019 Loan Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 Carrying Value (1) Maturity Date (2) Mezzanine Loan — 15,000 3,500 3,500 September 2021 Mezzanine Loan (4b) — 88,466 12,692 19,936 November 2023 Mezzanine Loan (4c) — 115,000 12,925 24,916 June 2024 Mezzanine Loan — 95,000 30,000 30,000 January 2025 Mezzanine Loan — 340,000 15,000 — November 2026 Mezzanine Loan (6) — — — 72,102 Mezzanine Loan (7) — — — 49,691 Jr. Mortgage Participation (8) — — — 49,000 Other (8)(9) — — — 23,510 Other (8)(9) — — — 66,183 Total fixed rate $ — $ 2,264,566 $ 360,359 $ 511,389 Floating Rate Investments: Mortgage/Mezzanine Loan (4d)(10) 36,042 — 145,239 134,264 January 2017 Mezzanine Loan (11) — 118,949 29,998 28,551 January 2017 Mezzanine Loan (4e)(12) — 40,000 15,369 68,977 June 2017 Mortgage/Mezzanine Loan — — 32,847 — June 2017 Mortgage/Mezzanine Loan — — 22,959 22,877 July 2017 Mortgage/Mezzanine Loan — — 16,960 16,901 September 2017 Mortgage/Mezzanine Loan 3,479 — 20,423 19,282 October 2017 Mezzanine Loan — 60,000 14,957 14,904 November 2017 Mezzanine Loan (4f) — 85,000 15,141 29,505 December 2017 Mezzanine Loan (4g) — 65,000 14,656 28,563 December 2017 Mortgage/Mezzanine Loan (4h) 795 — 15,051 14,942 December 2017 Jr. Mortgage Participation — 40,000 19,913 19,846 April 2018 Mezzanine Loan — 175,000 34,844 34,725 April 2018 Mortgage/Mezzanine Loan (13) 523 20,523 10,863 31,210 August 2018 Mortgage Loan — — 19,840 — August 2018 Mezzanine Loan — 65,000 14,880 — August 2018 Mezzanine Loan — 37,500 14,648 — September 2018 Mezzanine Loan 2,324 45,025 34,502 — October 2018 Mezzanine Loan — 335,000 74,476 — November 2018 Mezzanine Loan — 33,000 26,850 26,777 December 2018 Mezzanine Loan 3,317 165,326 56,114 52,774 December 2018 Mezzanine Loan 15,794 259,229 63,137 49,625 December 2018 Mezzanine Loan 14,715 199,935 64,505 — December 2018 Mezzanine Loan — 45,000 12,104 — January 2019 Mezzanine Loan 6,383 16,383 5,410 — January 2019 Mezzanine Loan — 38,000 21,891 21,845 March 2019 Mezzanine Loan — 265,000 24,707 — April 2019 Mortgage/Jr. Mortgage Participation Loan 33,573 183,300 65,554 — August 2019 Mezzanine Loan 2,500 187,500 37,322 — September 2019 Mortgage/Mezzanine Loan 82,888 — 111,819 — September 2019 Mortgage/Mezzanine Loan 35,630 — 33,682 — January 2020 Loan Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 Carrying Value (1) Maturity Date (2) Mezzanine Loan (14) 32,502 445,483 125,911 — January 2020 Jr. Mortgage Participation/Mezzanine Loan — 30,000 15,606 — July 2021 Mezzanine Loan (15) — — — 49,751 Mezzanine Loan (15) — — — 13,731 Mezzanine Loan (16) — — — 99,530 Mortgage/Mezzanine Loan (17) — — — 94,901 Jr. Mortgage Participation/Mezzanine Loan (6) — — — 20,510 Mezzanine Loan (18) — — — 22,625 Mezzanine Loan (19) — — — 74,700 Mezzanine Loan (20) — — — 66,398 Jr. Mortgage Participation/Mezzanine Loan (8) — — — 18,395 Mezzanine Loan (21) — — — 40,346 Total floating rate $ 270,465 $ 2,955,153 $ 1,232,178 $ 1,116,455 Total $ 270,465 $ 5,219,719 $ 1,592,537 $ 1,627,844 ____________________________________________________________________ (1) Carrying value is net of discounts, premiums, original issue discounts and deferred origination fees. (2) Represents contractual maturity, excluding any unexercised options. (3) This loan was refinanced at maturity in March 2017 by us at market rates, and therefore it was not considered a troubled-debt restructuring. (4) Carrying value is net of the following amount that was participated out, which is included in other assets and other liabilities on the consolidated balance sheets as a result of the transfer not meeting the conditions for sale accounting: (a) $41.3 million , (b) $5.0 million , (c) $12.0 million , (d) $36.3 million , (e) $14.5 million , (f) $14.6 million , (g) $14.1 million , and (h) $5.1 million . (5) In September 2014, we acquired a $26.4 million mortgage loan at a $0.2 million discount and a $5.7 million junior mortgage participation at a $5.7 million discount. The junior mortgage participation was a nonperforming loan at acquisition and is currently on non-accrual status. (6) This loan was repaid in July 2016. (7) In April 2016 we executed a purchase option to acquire a 20% interest in the underlying asset at a previously agreed upon purchase option valuation, and our mezzanine loan was simultaneously repaid. (8) This loan was repaid in March 2016. (9) This loan was collateralized by defeasance securities. (10) This loan was refinanced at maturity in January 2017 by us at market rates, and therefore it was not considered a troubled-debt restructuring. (11) This loan was extended in January 2017. (12) In March 2016, the mortgage was sold. (13) In January 2016, the loans were modified. In March 2016, the mortgage was sold. (14) $66.1 million of outstanding principal was syndicated in February 2017. (15) This loan was repaid in December 2016. (16) This loan was repaid in November 2016. (17) This loan was repaid in September 2016. (18) This loan was repaid in June 2016. (19) This loan was repaid in May 2016. (20) In March 2016, we contributed our interest in the loan in exchange for a joint venture interest which is now accounted for under the equity method of accounting. It is included in unconsolidated joint ventures on the consolidated balance sheets. (21) This loan was repaid in February 2016.
Schedule of preferred equity investments	As of December 31, 2016 and 2015 , we held the following preferred equity investments with an aggregate weighted average current yield of 8.16% at December 31, 2016 (in thousands): Type December 31, 2016 Future Funding Obligations December 31, 2016 Senior Financing December 31, 2016 Carrying Value (1) December 31, 2015 (1) Mandatory Redemption (2) Preferred Equity $ — $ 71,486 $ 9,982 $ 9,967 March 2018 Preferred Equity — 58,786 37,893 32,209 November 2018 $ — $ 130,272 $ 47,875 $ 42,176 ____________________________________________________________________ (1) Carrying value is net of deferred origination fees. (2) Represents contractual maturity, excluding any unexercised extension options. The following table is a rollforward of our total loan loss reserves at December 31, 2016 , 2015 and 2014 (in thousands): Year Ended December 31, 2016 2015 2014 Balance at beginning of year $ — $ — $ 1,000 Expensed — — — Recoveries — — — Charge-offs and reclassifications — — (1,000 ) Balance at end of period $ — $ — $ —

Investments in Unconsolidated35

Investments in Unconsolidated Joint Ventures (Tables)	12 Months Ended
	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Schedule of investment in real estate joint venture	The table below provides general information on each of our joint ventures as of December 31, 2016 : Property Partner Ownership Interest (1) Economic Interest (1) Approximate Square Feet Acquisition Date (2) Acquisition Price (2) (in thousands) 131-137 Spring Street Invesco Real Estate 20.00% 20.00% 68,342 August 2015 $ 277,750 76 11th Avenue (3) Oxford/Vornado 33.33% 35.09% 764,000 March 2016 138,240 (1) Ownership interest and economic interest represent the Company's interests in the joint venture as of December 31, 2016 . Changes in ownership or economic interests within the current year are disclosed in the notes below. (2) Acquisition date and price represent the date on which the Company initially acquired an interest in the joint venture and the actual or implied gross purchase price for the joint venture on that date. Acquisition date and price are not adjusted for subsequent acquisitions or dispositions of interest. (3) The joint venture owns two mezzanine notes secured by interests in the entity that owns 76 11th Avenue. The difference between our ownership interest and our economic interest results from our right to 50% of the total exit fee while each of our partners is entitled to receive 25% of the total exit fee and our right to 38% of the total extension fee while each of our partners is entitled to receive 31% of the total extension fee. As of December 31, 2016 and 2015 , the carrying value for acquisition, development and construction arrangements were as follows (in thousands): Loan Type December 31, 2016 December 31, 2015 Maturity Date Mezzanine Loan and Preferred Equity (1) $ 100,000 $ 99,936 March 2017 Mezzanine Loan (2) 24,542 — July 2036 $ 124,542 $ 99,936 (1) This loan was extended in March 2017. (2) The Company has the ability to convert this loan into an equity position starting in 2021 and the borrower is able to force this conversion in 2024.
Schedule of Mortgage and Other Loans Payable on Joint Venture Properties	The first mortgage notes and other loans payable collateralized by the respective joint venture properties and assignment of leases at December 31, 2016 and December 31, 2015 , respectively, are as follows (amounts in thousands): Property Maturity Date Interest Rate (1) December 31, 2016 December 31, 2015 Floating Rate Debt: 131-137 Spring Street August 2020 2.03 % $ 141,000 $ 141,000 Total joint venture mortgages and other loans payable $ 141,000 $ 141,000 Deferred financing costs, net (3,970 ) (5,077 ) Total joint venture mortgages and other loans payable, net $ 137,030 $ 135,923 (1) Effective weighted average interest rate for the year ended December 31, 2016 , taking into account interest rate hedges in effect during the period.
Equity Method Investments, Summarized Financial Information Balance Sheet	The combined balance sheets for the unconsolidated joint ventures, at December 31, 2016 and December 31, 2015 are as follows (in thousands): December 31, 2016 December 31, 2015 Assets Commercial real estate property, net $ 279,451 $ 285,689 Debt and preferred equity investments, net 273,749 99,936 Other assets 18,922 16,897 Total assets $ 572,122 $ 402,522 Liabilities and members' equity Mortgages and other loans payable, net $ 137,030 $ 135,923 Other liabilities 22,185 25,462 Members' equity 412,907 241,137 Total liabilities and members' equity $ 572,122 $ 402,522 Company's investments in unconsolidated joint ventures $ 174,127 $ 100,192
Equity Method Investments, Summarized Financial Information Income Statement	The combined statements of operations for the unconsolidated joint ventures for the years ended December 31, 2016 , 2015 , and 2014 are as follows (in thousands): Year Ended December 31, 2016 2015 2014 Total revenues $ 38,524 $ 19,855 $ 7,121 Operating expenses 1,238 1,686 59 Real estate taxes 1,192 1,262 — Interest expense, net of interest income 2,895 1,070 — Amortization of deferred financing costs 1,108 462 — Transaction related costs — 5,262 181 Depreciation and amortization 8,404 3,207 — Total expenses $ 14,837 $ 12,949 $ 240 Net income $ 23,687 $ 6,906 $ 6,881 Company's equity in net income from unconsolidated joint ventures 14,509 8,841 4,491

Mortgages and Other Loans Pay36

Mortgages and Other Loans Payable (Tables)	12 Months Ended
	Dec. 31, 2016
Mortgage Note and Other Loans Payable
Schedule of the first mortgage note and other loans payable collateralized by the property, assignment of leases and investment	The first mortgages and other loans payable collateralized by the respective properties and assignment of leases at December 31, 2016 and 2015 , respectively, were as follows (amounts in thousands): Property Maturity Date Interest Rate (1) December 31, 2016 December 31, 2015 Fixed Rate Debt: 919 Third Avenue (2) June 2023 5.12 % $ 500,000 $ 500,000 Floating Rate Debt: Master Repurchase Agreement July 2018 3.04 % $ 184,642 $ 253,424 Total mortgages and other loans payable $ 684,642 $ 753,424 Deferred financing costs, net of amortization (8,574 ) (7,696 ) Total fixed and floating rate debt $ 676,068 $ 745,728 ____________________________________________________________________ (1) Effective weighted average interest rate for the year ended December 31, 2016 . (2) We own a 51.0% controlling interest in the joint venture that is the borrower on this loan.

Corporate Indebtedness (Tables)

Corporate Indebtedness (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule of senior unsecured notes and other related disclosures by scheduled maturity date	The following table sets forth our senior unsecured notes and other related disclosures as of December 31, 2016 and 2015 , respectively, by scheduled maturity date (dollars in thousands): Issuance December 31, 2016 December 31, 2016 December 31, 2015 Coupon (1) Effective Rate Term (in Years) Maturity Date August 5, 2011 (2) $ 250,000 $ 249,880 $ 249,810 5.00 % 5.00 % 7 August 2018 March 16, 2010 (2) 250,000 250,000 250,000 7.75 % 7.75 % 10 March 2020 November 15, 2012 (2) 200,000 200,000 200,000 4.50 % 4.50 % 10 December 2022 December 17, 2015 (2) 100,000 100,000 100,000 4.27 % 4.27 % 10 December 2025 March 31, 2006 (3) — — 255,296 $ 800,000 $ 799,880 $ 1,055,106 Deferred financing costs, net (4,620 ) (5,303 ) $ 800,000 $ 795,260 $ 1,049,803 ______________________________________________________________________ (1) Interest on the senior unsecured notes is payable semi-annually with principal and unpaid interest due on the scheduled maturity dates. (2) Issued by SL Green, the Operating Partnership and ROP, as co-obligors. (3) This note was repaid in March 2016.
Schedule of Combined aggregate principal maturities of mortgage and other loans payable, 2012 credit facility and senior unsecured notes, including as-of-right extension options	Combined aggregate principal maturities of our mortgage and other loans payable, 2012 credit facility and senior unsecured notes as of December 31, 2016 , including as-of-right extension options and put options, were as follows (in thousands): Scheduled Principal Revolving Unsecured Term Loan Senior Total 2017 $ — $ — $ — $ — $ — $ — 2018 — 184,642 — — 250,000 $ 434,642 2019 — — — 1,183,000 — $ 1,183,000 2020 — — — — 250,000 $ 250,000 2021 — — — — — $ — Thereafter — 500,000 — — 300,000 $ 800,000 $ — $ 684,642 $ — $ 1,183,000 $ 800,000 $ 2,667,642
Schedule of Consolidated Interest expense, excluding capitalized interest	Consolidated interest expense, excluding capitalized interest, was comprised of the following (in thousands): Year Ended December 31, 2016 2015 2014 Interest expense before capitalized interest $ 110,393 $ 120,467 $ 133,180 Interest capitalized (1,171 ) (1,107 ) (3,753 ) Interest income (14 ) (18 ) (71 ) Interest expense, net $ 109,208 $ 119,342 $ 129,356

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value, by Balance Sheet Grouping	The following table provides the carrying value and fair value of these financial instruments as of December 31, 2016 and 2015 (in thousands): December 31, 2016 December 31, 2015 Carrying Value (1) Fair Value Carrying Value (1) Fair Value Debt and preferred equity investments (2) $ 1,640,412 (3) $ 1,670,020 (3) Fixed rate debt $ 2,099,880 $ 2,183,042 $ 1,585,106 $ 1,663,078 Variable rate debt 567,642 580,083 2,150,424 2,164,673 $ 2,667,522 $ 2,763,125 $ 3,735,530 $ 3,827,751 ______________________________________________________________________ (1) Amounts exclude net deferred financing costs. (2) Excludes investment with a book value of $174.1 million and $100.2 million as of December 31, 2016 and 2015 , respectively, which we accounted for under the equity method accounting as a result of meeting the criteria of a real estate investment under the guidance for Acquisition, Development and Construction arrangements, and other investments with a book value of $144.5 million and $168.3 million as of December 31, 2016 and 2015 , respectively. (3) At December 31, 2016 , debt and preferred equity investments had an estimated fair value ranging between $1.6 billion and $1.8 billion . At December 31, 2015 , debt and preferred equity investments had an estimated fair value ranging between $1.7 billion and $1.8 billion .

Financial Instruments_ Deriva39

Financial Instruments: Derivatives and Hedging (Tables)	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of effect of derivative financial instruments on consolidated statements of income	The following table presents the effect of our derivative financial instruments that are designated and qualify as hedging instruments on the consolidated statements of operations for the years ended December 31, 2016 , 2015 , and 2014 , respectively (in thousands): Amount of Loss Recognized in Other Comprehensive Loss (Effective Portion) Location of Loss Reclassified from Accumulated Other Comprehensive Loss into Income Amount of Loss Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion) Location of Gain Recognized in Income on Derivative Amount of Gain Recognized into Income (Ineffective Portion) Year Ended December 31, Year Ended December 31, Year Ended December 31, Derivative 2016 2015 2014 2016 2015 2014 2016 2015 2014 Interest Rate Swap $ (13 ) $ (109 ) $ (135 ) Interest expense $ 611 $ 999 $ 970 Interest expense $ 3 $ 3 $ 4

Rental Income (Tables)

Rental Income (Tables)	12 Months Ended
	Dec. 31, 2016
Leases [Abstract]
Schedule of approximate future minimum rents to be received over the next five years and thereafter	Approximate future minimum rents to be received over the next five years and thereafter for non-cancelable operating leases in effect at December 31, 2016 for the consolidated properties, including consolidated joint venture properties, are as follows (in thousands): 2017 $ 622,264 2018 602,291 2019 567,694 2020 501,107 2021 447,588 Thereafter 2,173,526 $ 4,914,470

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Schedule of contributions made to multi-employer plans	Contributions we made to the multi-employer plans for the years ended December 31, 2016 , 2015 and 2014 are included in the table below (in thousands): Year Ended December 31, 2016 2015 2014 Pension Plan $ 2,219 $ 1,533 $ 1,529 Health Plan 6,366 4,843 4,585 Other plans 902 3,300 3,181 Total plan contributions $ 9,487 $ 9,676 $ 9,295

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum lease payments under capital leases and noncancellable operating leases	The following is a schedule of future minimum lease payments under non-cancellable operating leases with initial terms in excess of one year as of December 31, 2016 (in thousands): Non-cancellable operating leases 2017 $ 20,586 2018 20,586 2019 20,586 2020 20,586 2021 20,736 Thereafter 308,202 Total minimum lease payments $ 411,282

Quarterly Financial Data of t43

Quarterly Financial Data of the Company (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	Summarized quarterly financial data for the years ended December 31, 2016 and 2015 , was as follows (in thousands): 2016 Quarter Ended December 31 September 30 June 30 March 31 Total revenues $ 232,658 $ 271,336 $ 231,758 $ 239,664 Income from continuing operations before equity in net income from unconsolidated joint ventures, and loss on sale of real estate $ 66,056 $ 98,647 $ 71,254 $ 69,743 Equity in net income from unconsolidated joint ventures 4,110 4,276 3,666 2,457 Loss on sale of real estate (10 ) — (6,899 ) — Net income 70,156 102,923 68,021 72,200 Net income attributable to noncontrolling interests in other partnerships (1,071 ) (1,279 ) (2,062 ) (12 ) Preferred units dividend (956 ) (955 ) (955 ) (955 ) Net income attributable to ROP common unitholder $ 68,129 $ 100,689 $ 65,004 $ 71,233 2015 Quarter Ended December 31 September 30 June 30 March 31 Total revenues $ 238,283 $ 237,651 $ 234,631 $ 214,668 Income from continuing operations before equity in net income from unconsolidated joint ventures, (loss) gain on sale of real estate, depreciable real estate reserves, unrealized gain (loss) on embedded derivative and loss on extinguishment of debt $ 69,152 $ 65,541 $ 76,236 $ 52,851 Equity in net income from unconsolidated joint ventures 2,265 2,296 2,153 2,127 (Loss) gain on sale of real estate (879 ) 101,069 — — Depreciable real estate reserves — (9,998 ) — — Unrealized gain (loss) on embedded derivative 1,800 (1,800 ) — — Loss on extinguishment of debt — — — (49 ) Net income 72,338 157,108 78,389 54,929 Net income attributable to noncontrolling interests in other partnerships (1,946 ) (293 ) (6,380 ) (550 ) Preferred units dividend (955 ) (743 ) — — Net income attributable to ROP common unitholder $ 69,437 $ 156,072 $ 72,009 $ 54,379

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Schedule of Selected results of operations and selected asset information	Selected results of operations for the years ended December 31, 2016 , 2015 and 2014 and selected asset information as of December 31, 2016 and 2015 , regarding our operating segments are as follows (in thousands): Real Estate Segment Debt and Preferred Equity Segment Total Company Total revenues: Years ended: December 31, 2016 $ 750,233 $ 225,183 $ 975,416 December 31, 2015 721,697 203,536 925,233 December 31, 2014 647,555 199,967 847,522 Income from continuing operations, equity in net gain on sale of interest in unconsolidated joint venture, (loss) gain on sale of real estate, depreciable real estate reserves and loss on early extinguishment of debt Years ended: December 31, 2016 $ 118,199 $ 202,010 $ 320,209 December 31, 2015 96,821 175,800 272,621 December 31, 2014 34,821 170,668 205,489 Total assets As of: December 31, 2016 $ 6,786,479 $ 1,968,134 $ 8,754,613 December 31, 2015 6,791,377 2,041,940 8,833,317
Schedule of reconciliation of income from continuing operations to net income attributable to SL Green common stockholders	The table below reconciles income from continuing operations to net income for the years ended December 31, 2016 , 2015 and 2014 (in thousands): Year ended December 31, 2016 2015 2014 Income from continuing operations before equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, depreciable real estate reserves, and loss on early extinguishment of debt. $ 320,209 $ 272,621 $ 205,489 Equity in net gain on sale of interest in unconsolidated joint venture/real estate — — 85,559 (Loss) gain on sale of real estate (6,909 ) 100,190 — Depreciable real estate reserves — (9,998 ) — Loss on early extinguishment of debt — (49 ) (7,385 ) Income from continuing operations 313,300 362,764 283,663 Net income from discontinued operations — — 1,996 Gain on sale of discontinued operations — — 117,579 Net income $ 313,300 $ 362,764 $ 403,238

Organization and Basis of Pre45

Organization and Basis of Presentation (Details) $ in Millions	1 Months Ended		12 Months Ended
	Jan. 31, 2017USD ($)	Aug. 31, 2015USD ($)ft²	Dec. 31, 2016USD ($)ft²property	Dec. 31, 2015USD ($)property	Dec. 31, 2014USD ($)property
Real estate properties
Percentage of ownership in SL Green Operating Partnership owned by SL Green Realty Corp (as a percent)			95.84%
Number of Properties Transferred by Parent Company | property				2	5
Carrying value of properties transferred by SL Green | $				$ 395	$ 884.3
Number of Entities Transferred by Parent Company | property				1
Carrying value of entities transferred by the parent company | $				$ 1,700
Number of Properties | property			42
Approximate Square Feet (sqft)			12,539,646
Weighted Average Occupancy (as a percent)			93.00%
Mortgage Loans on Real Estate, Commercial and Consumer, Net Including Debt Investments, Other | $			$ 2,000
Debt Investments, Other | $			$ 300
131-137 Spring Street
Real estate properties
Approximate Square Feet (sqft)		68,342
Sales Price | $		$ 277.8
Suburban
Real estate properties
Number of Properties | property			19
Approximate Square Feet (sqft)			3,303,000
Weighted Average Occupancy (as a percent)			83.40%
Office | Manhattan
Real estate properties
Number of Properties | property			16
Approximate Square Feet (sqft)			8,463,245
Weighted Average Occupancy (as a percent)			96.40%
Office | Suburban
Real estate properties
Number of Properties | property			18
Approximate Square Feet (sqft)			3,251,000
Weighted Average Occupancy (as a percent)			83.20%
Retail | 131-137 Spring Street
Real estate properties
Approximate Square Feet (sqft)			68,342
Number of properties held for sale | property			2
Retail | Manhattan
Real estate properties
Number of Properties | property			5
Approximate Square Feet (sqft)			352,892
Weighted Average Occupancy (as a percent)			97.60%
Retail | Suburban
Real estate properties
Number of Properties | property			1
Approximate Square Feet (sqft)			52,000
Weighted Average Occupancy (as a percent)			100.00%
Fee Interest | Manhattan
Real estate properties
Number of Properties | property			2
Approximate Square Feet (sqft)			197,654
Weighted Average Occupancy (as a percent)			100.00%
Commercial Properties
Real estate properties
Number of Properties | property			42
Approximate Square Feet (sqft)			12,316,791
Weighted Average Occupancy (as a percent)			93.00%
Commercial Properties | Manhattan
Real estate properties
Number of Properties | property			23
Approximate Square Feet (sqft)			9,013,791
Weighted Average Occupancy (as a percent)			96.50%
Residential | Manhattan
Real estate properties
Number of Properties | property			0
Approximate Square Feet (sqft)			222,855
Weighted Average Occupancy (as a percent)			93.10%
Consolidated Properties | Dual property type, retail portion | Manhattan
Real estate properties
Approximate Square Feet (sqft)			270,132
Consolidated Properties | Dual property type, residential portion | Manhattan
Real estate properties
Approximate Square Feet (sqft)			222,855
Subsequent Event | 520 White Plains Road
Real estate properties
Sales Price | $	$ 21
Loss on disposal of property | $	$ 11.1

Significant Accounting Polici46

Significant Accounting Policies (Details)	1 Months Ended	3 Months Ended				12 Months Ended
	Mar. 31, 2014USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)property	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Investment in Commercial Real Estate Properties
Commercial real estate property, net		$ 6,160,645,000				$ 6,071,648,000	$ 6,160,645,000
Depreciation expense (including amortization of capital lease asset)						196,200,000	187,200,000	$ 184,300,000
Impairment charge		0	$ (9,998,000)	$ 0	$ 0	$ 0	(9,998,000)	0
Number of properties expected to be sold | property			1
Maximum period of cessation of major construction activity to completion of construction project (in years)						1 year
Weighted average amortization period, above-market leases (in years)						4 years 1 month 6 days
Weighted average amortization period, below-market leases (in years)						28 years 9 months 18 days
Weighted average amortization period, in-place leases (in years)						11 years 3 months 18 days
Rental revenue from amortization of acquired leases						$ 20,200,000	24,900,000	21,000,000
Increase (reduction) in interest expense from amortization of above-market rate mortgages						100,000	400,000	$ 2,100,000
Identified intangible assets (included in other assets):
Gross amount		307,824,000				311,830,000	307,824,000
Accumulated amortization		(235,040,000)				(253,064,000)	(235,040,000)
Net		72,784,000				58,766,000	72,784,000
Identified intangible liabilities (included in deferred revenue):
Gross amount		523,228,000				524,793,000	523,228,000
Accumulated amortization		(346,857,000)				(368,738,000)	(346,857,000)
Net		176,371,000				156,055,000	176,371,000
Net Intangible Assets Transferred to Assets Held for Sale						0
Net Intangible Liabilities Transferred to Liabilities Related to Assets Held for Sale						$ 0
16 Court Street
Investment in Commercial Real Estate Properties
Income from amortization of remaining value of below-market mortgage	$ 300,000
Above-market leases | Minimum
Investment in Commercial Real Estate Properties
Estimated useful life of intangible assets (years)						1 year
Above-market leases | Maximum
Investment in Commercial Real Estate Properties
Estimated useful life of intangible assets (years)						14 years
Below-market leases | Minimum
Investment in Commercial Real Estate Properties
Estimated useful life of intangible assets (years)						1 year
Below-market leases | Maximum
Investment in Commercial Real Estate Properties
Estimated useful life of intangible assets (years)						14 years
In-place leases | Minimum
Investment in Commercial Real Estate Properties
Estimated useful life of intangible assets (years)						1 year
In-place leases | Maximum
Investment in Commercial Real Estate Properties
Estimated useful life of intangible assets (years)						14 years
Building Fee Ownership
Investment in Commercial Real Estate Properties
Estimated useful life (years)						40 years
Building (leasehold interest) | Maximum
Investment in Commercial Real Estate Properties
Estimated useful life (years)						40 years
Furniture and fixtures | Minimum
Investment in Commercial Real Estate Properties
Estimated useful life (years)						4 years
Furniture and fixtures | Maximum
Investment in Commercial Real Estate Properties
Estimated useful life (years)						7 years
Building | Minimum
Investment in Commercial Real Estate Properties
Estimated useful life (years)						3 years
Building | Maximum
Investment in Commercial Real Estate Properties
Estimated useful life (years)						40 years
140 Grand Street
Investment in Commercial Real Estate Properties
Impairment charge			$ (10,000,000)
Variable Interest Entity, Primary Beneficiary [Member]
Investment in Commercial Real Estate Properties
Commercial real estate property, net		0				$ 1,400,000,000	0
Mortgages and other loans payable, net		$ 0				$ 494,100,000	$ 0

Significant Accounting Polici47

Significant Accounting Policies (Estimated Annual Amortization and Revenue Recognition)(Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Rental revenue from amortization of acquired leases	$ 20,200	$ 24,900	$ 21,000
Revenue Recognition
Period after which payments become due (days)	90 days
Lease Agreements
Below Market Lease, Net, Amortization Income, Fiscal Year Maturity [Abstract]
2,017	$ (15,745)
2,018	(13,628)
2,019	(13,135)
2,020	(12,342)
2,021	(3,831)
Other Identifiable Assets
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,017	14,403
2,018	9,195
2,019	7,519
2,020	6,617
2,021	$ 3,719

Significant Accounting Polici48

Significant Accounting Policies (Concentrations of Credit Risk and Reclassification)(Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Concentrations of Credit Risk
Debt Issuance Costs, Net	$ 22.8	$ 25.2
Annualized cash rent | Customer concentration
Concentrations of Credit Risk
Maximum percentage of annualized cash rent for any one tenant not individually disclosed (more than)	5.00%
Annualized cash rent | Customer concentration | 919 Third Avenue
Concentrations of Credit Risk
Percentage of concentration	13.50%	8.20%	8.60%
Annualized cash rent | Customer concentration | 1185 Avenue of the Americas
Concentrations of Credit Risk
Percentage of concentration	12.60%	15.40%	17.40%
Annualized cash rent | Customer concentration | 625 Madison Avenue
Concentrations of Credit Risk
Percentage of concentration	8.20%	9.70%	9.40%
Annualized cash rent | Customer concentration | 750 Third Avenue
Concentrations of Credit Risk
Percentage of concentration	6.60%	7.70%	8.70%
Annualized cash rent | Customer concentration | 810 Seventh Avenue
Concentrations of Credit Risk
Percentage of concentration	6.20%	7.50%
Annualized cash rent | Customer concentration | 555 W. 57th Street
Concentrations of Credit Risk
Percentage of concentration	5.60%	6.70%
Annualized cash rent | Customer concentration | 1350 Avenue of the Americas
Concentrations of Credit Risk
Percentage of concentration	5.50%	7.20%	7.80%
Annualized cash rent | Customer concentration | 125 Park Avenue
Concentrations of Credit Risk
Percentage of concentration	5.60%	6.60%

Property Acquisitions (Details)

Property Acquisitions (Details) - USD ($) $ in Thousands	1 Months Ended				12 Months Ended
	Jul. 31, 2015	Oct. 31, 2014	Sep. 30, 2014	Jul. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Impact to rental revenue for amortization of aggregate below-market leases					$ 652,629	$ 621,121	$ 574,150
Impact to depreciation expense					212,514	202,474	$ 196,505
110 Greene Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land	$ 45,120
Building and building leasehold	215,470
Above-market lease value	0
Acquired in-place lease value	8,967
Other assets, net of other liabilities	0
Assets acquired	269,557
Mark-to-market assumed debt	0
Below-market lease value	(14,557)
Derivatives	0
Liabilities assumed	(14,557)
Purchase price	255,000
Net consideration funded by us at closing, excluding consideration financed by debt	255,000
Equity and/or debt investment held	0
Debt assumed	$ 0
Impact to rental revenue for amortization of aggregate below-market leases					1,600
Impact to depreciation expense					$ 3,100
Ownership interest in consolidated joint venture (as a percent)	90.00%
102 Greene Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land		$ 8,215
Building and building leasehold		26,717
Above-market lease value		0
Acquired in-place lease value		1,015
Other assets, net of other liabilities		3
Assets acquired		35,950
Mark-to-market assumed debt		0
Below-market lease value		(3,701)
Liabilities assumed		(3,701)
Purchase price		32,249
Net consideration funded by us at closing, excluding consideration financed by debt		32,249
Equity and/or debt investment held		0
Debt assumed		0
635 Madison Avenue
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land			$ 205,632
Building and building leasehold			15,805
Above-market lease value			0
Acquired in-place lease value			17,345
Other assets, net of other liabilities			0
Assets acquired			238,782
Mark-to-market assumed debt			0
Below-market lease value			(85,036)
Liabilities assumed			(85,036)
Purchase price			153,746
Net consideration funded by us at closing, excluding consideration financed by debt			153,746
Equity and/or debt investment held			0
Debt assumed			0
115 Spring Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land				$ 11,078
Building and building leasehold				44,799
Above-market lease value				0
Acquired in-place lease value				2,037
Other assets, net of other liabilities				0
Assets acquired				57,914
Mark-to-market assumed debt				0
Below-market lease value				(4,789)
Liabilities assumed				(4,789)
Purchase price				53,125
Net consideration funded by us at closing, excluding consideration financed by debt				53,125
Equity and/or debt investment held				0
Debt assumed				0
Impact to rental revenue for amortization of aggregate below-market leases						1,900
Impact to depreciation expense						$ 1,100
Scenario, Previously Reported | 110 Greene Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land	$ 89,300
Building and building leasehold	165,800
Scenario, Previously Reported | 102 Greene Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land		11,300
Building and building leasehold		$ 21,000
Scenario, Previously Reported | 635 Madison Avenue
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land			$ 153,700
Scenario, Previously Reported | 115 Spring Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Land				15,900
Building and building leasehold				$ 37,200
Series P Preferred Units | 110 Greene Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Issuance of aggregate liquidation preference of preferred units	5,000
Series Q Preferred Units | 110 Greene Street
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed
Issuance of aggregate liquidation preference of preferred units	$ 6,700

Property Held for Sale and Di50

Property Held for Sale and Dispositions (Details) $ in Thousands	1 Months Ended				3 Months Ended				12 Months Ended
	May 31, 2016USD ($)a	Dec. 31, 2015USD ($)ft²	Aug. 31, 2015USD ($)ft²	May 31, 2014USD ($)ft²	Dec. 31, 2015USD ($)ft²	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)ft²	Dec. 31, 2015USD ($)ft²	Dec. 31, 2014USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Approximate Usable Square Feet (sqft) | ft²									12,539,646
Gain (loss) on Sale									$ 0	$ 0	$ 117,579
Impairment charge					$ 0	$ 9,998	$ 0	$ 0	0	9,998	0
Revenues
Rental revenue									0	0	7,853
Escalation and reimbursement revenues									0	0	1,080
Other income									0	0	0
Total revenues									0	0	8,933
Operating expenses									0	0	1,222
Real estate taxes									0	0	1,402
Ground rent									0	0	3,001
Interest expense, net of interest income									0	0	879
Depreciation and amortization									0	0	433
Total expenses									0	0	6,937
Net income from discontinued operations									$ 0	$ 0	$ 1,996
7 International Drive
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Approximate Usable Square Feet (sqft) | a	31
Sales Price	$ 20,000
Gain (loss) on Sale	$ (6,900)
140 Grand Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Approximate Usable Square Feet (sqft) | ft²		130,100			130,100					130,100
Sales Price		$ 22,400
Gain (loss) on Sale		$ (10,500)
Impairment charge						$ 10,000
131-137 Spring Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Approximate Usable Square Feet (sqft) | ft²			68,342
Sales Price			$ 277,800
Gain (loss) on Sale			101,100
Employee compensation awards accrued			$ 4,100
Ownership percentage in disposed asset			80.00%
673 First Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Approximate Usable Square Feet (sqft) | ft²				422,000
Sales Price				$ 145,000
Gain (loss) on Sale				117,600
Employee compensation awards accrued				$ 3,400

Debt and Preferred Equity Inv51

Debt and Preferred Equity Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Apr. 30, 2016	Sep. 30, 2014
Debt investment
Increase in debt and preferred equity investments (net of discounts), including investments classified as held-for-sale	$ 1,015,000	$ 781,000
Decrease in debt and preferred equity investments (net of discounts), including investments classified as held-for-sale	$ 1,045,000	520,000
Aggregate weighted average current yield (as a percent)	9.34%
Mezzanine Loan, June 2017
Debt Investments Held [Abstract]
Amount participated out	$ 41,300
Mezzanine Loan, November 2023
Debt Investments Held [Abstract]
Amount participated out	5,000
Mezzanine Loan with an Initial Maturity Date of June 2024 [Member]
Debt Investments Held [Abstract]
Amount participated out	12,000
Mezzanine Loan Repaid in April 2016 [Member]
Debt Investments Held [Abstract]
Equity Method Investment, Ownership Percentage			20.00%
Mortgage/Mezzanine Loan, January 2017
Debt Investments Held [Abstract]
Amount participated out	36,300
Mezzanine Loan, December 2017
Debt Investments Held [Abstract]
Amount participated out	14,600
Mezzanine Loan with an Initial Maturity Date of December 2017, 2 [Member]
Debt Investments Held [Abstract]
Amount participated out	14,100
Mortgage/Mezzanine Loan, December 2017
Debt Investments Held [Abstract]
Amount participated out	5,100
Debt Investments in Mortgage Loans [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	270,465
Senior Financing	5,219,719
Carrying Value	1,592,537	1,627,844
Mezzanine Loan with an Initial Maturity Date of June 2017, 2 [Member]
Debt Investments Held [Abstract]
Amount participated out	14,500
Total fixed rate
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	2,264,566
Carrying Value	360,359	511,389
Total fixed rate | Junior Mortgage Participation/Mezzanine Loan, March 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	1,109,000
Carrying Value	193,422	104,661
Total fixed rate | Mezzanine Loan, June 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	502,100
Carrying Value	66,129	41,115
Total fixed rate | Mortgage Loan, February 2019
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	26,311	26,262
Loan acquired				$ 26,400
Discount amount				200
Total fixed rate | Mortgage Loan, August 2019
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	380	513
Total fixed rate | Mezzanine Loan, September 2021
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	15,000
Carrying Value	3,500	3,500
Total fixed rate | Mezzanine Loan, November 2023
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	88,466
Carrying Value	12,692	19,936
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of June 2024 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	115,000
Carrying Value	12,925	24,916
Total fixed rate | Mezzanine Loan, January 2025
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	95,000
Carrying Value	30,000	30,000
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of November 2026 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	340,000
Carrying Value	15,000	0
Total fixed rate | Mezzanine Loan Repaid in July 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	72,102
Total fixed rate | Mezzanine Loan Repaid in April 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	49,691
Total fixed rate | Junior Mortgage Participation Loan Repaid in March 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	49,000
Total fixed rate | Loan Collateralized by Defeasance Securities Repaid in March 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	23,510
Total fixed rate | Loan Collateralized by Defeasance Securities Repaid in March 2016, 2 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	66,183
Total fixed rate | Junior Mortgage Participation, Related To Mortgage Loan, February 2019
Debt Investments Held [Abstract]
Loan acquired				5,700
Discount amount				$ 5,700
Total floating rate
Debt Investments Held [Abstract]
Future Funding Obligations	270,465
Senior Financing	2,955,153
Carrying Value	1,232,178	1,116,455
Total floating rate | Mezzanine Loan, June 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	40,000
Carrying Value	15,369	68,977
Total floating rate | Mortgage/Mezzanine Loan, January 2017
Debt Investments Held [Abstract]
Future Funding Obligations	36,042
Senior Financing	0
Carrying Value	145,239	134,264
Total floating rate | Mezzanine Loan, January 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	118,949
Carrying Value	29,998	28,551
Total floating rate | Mortgage/Mezzanine Loan, June 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	32,847	0
Total floating rate | Mortgage/Mezzanine Loan with an Initial Maturity Date of July 2017 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	22,959	22,877
Total floating rate | Mortgage/Mezzanine Loan, September 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	16,960	16,901
Total floating rate | Mortgage/Mezzanine Loan, October 2017
Debt Investments Held [Abstract]
Future Funding Obligations	3,479
Senior Financing	0
Carrying Value	20,423	19,282
Total floating rate | Mezzanine Loan, November 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	60,000
Carrying Value	14,957	14,904
Total floating rate | Mezzanine Loan, December 2017
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	85,000
Carrying Value	15,141	29,505
Total floating rate | Mezzanine Loan with an Initial Maturity Date of December 2017, 2 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	65,000
Carrying Value	14,656	28,563
Total floating rate | Mortgage/Mezzanine Loan, December 2017
Debt Investments Held [Abstract]
Future Funding Obligations	795
Senior Financing	0
Carrying Value	15,051	14,942
Total floating rate | Junior Mortgage Participation, April 2018
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	40,000
Carrying Value	19,913	19,846
Total floating rate | Mezzanine Loan, April 2018
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	175,000
Carrying Value	34,844	34,725
Total floating rate | Mortgage/Mezzanine Loan, August 2018
Debt Investments Held [Abstract]
Future Funding Obligations	523
Senior Financing	20,523
Carrying Value	10,863	31,210
Total floating rate | Mortgage Loan with an Initial Maturity Date of August 2018 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	19,840	0
Total floating rate | Mezzanine Loan with an Initial Maturity Date of August 2018 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	65,000
Carrying Value	14,880	0
Total floating rate | Mezzanine Loan with an Initial Maturity Date of September 2018 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	37,500
Carrying Value	14,648	0
Total floating rate | Mezzanine Loan with an Initial Maturity Date of October 2018 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	2,324
Senior Financing	45,025
Carrying Value	34,502	0
Total floating rate | Mezzanine Loan with an Initial Maturity Date of November 2018 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	335,000
Carrying Value	74,476	0
Total floating rate | Mezzanine Loan, December 2018
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	33,000
Carrying Value	26,850	26,777
Total floating rate | Mezzanine Loan with an Initial Maturity Date of December 2018, 2 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	3,317
Senior Financing	165,326
Carrying Value	56,114	52,774
Total floating rate | Mezzanine Loan with an Initial Maturity Date of December 2018, 3 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	15,794
Senior Financing	259,229
Carrying Value	63,137	49,625
Total floating rate | Mezzanine Loan with an Initial Maturity Date of December 2018, 4 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	14,715
Senior Financing	199,935
Carrying Value	64,505	0
Total floating rate | Mezzanine Loan with an Initial Maturity Date of January 2019 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	45,000
Carrying Value	12,104	0
Total floating rate | Mezzanine Loan with an Initial Maturity Date of January 2019, 2 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	6,383
Senior Financing	16,383
Carrying Value	5,410	0
Total floating rate | Mezzanine Loan, March 2019
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	38,000
Carrying Value	21,891	21,845
Total floating rate | Mezzanine Loan with an Initial Maturity Date of April 2019 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	265,000
Carrying Value	24,707	0
Total floating rate | Mortgage/Jr Mortgage Participate Loan, Maturity Date of August 2019 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	33,573
Senior Financing	183,300
Carrying Value	65,554	0
Total floating rate | Mezzanine Loan, Maturity of September 2019 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	2,500
Senior Financing	187,500
Carrying Value	37,322	0
Total floating rate | Mortgage/Mezzanine Loan with an Initial Maturity of September 2019 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	82,888
Senior Financing	0
Carrying Value	111,819	0
Total floating rate | Mortgage/Mezzanine Loan with an Initial Maturity of January 2020 [Member] [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	35,630
Senior Financing	0
Carrying Value	33,682	0
Total floating rate | Mezzanine Loan with an Initial Maturity of January 2020 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	32,502
Senior Financing	445,483
Carrying Value	125,911	0
Amount participated out	66,100
Total floating rate | Jr Mortgage Participation/Mezzanine Loan with an Initial Maturity of July 2021 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	30,000
Carrying Value	15,606	0
Total floating rate | Debt investment
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	49,751
Total floating rate | Mezzanine Loan Repaid in December 2016, 2 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	13,731
Total floating rate | Mezzanine Loan Repaid in November 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	99,530
Total floating rate | Mortgage/Mezzanine Loan Repaid in September 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	94,901
Total floating rate | Jr Mortgage Participation/Mezzanine Loan Repaid in July 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	20,510
Total floating rate | Mezzanine Loan Repaid in June 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	22,625
Total floating rate | Mezzanine Loan Repaid in May 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	74,700
Total floating rate | Mezzanine Loan Contributed for a Joint Venture Interest [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	66,398
Total floating rate | Jr. Mortgage Participation/Mezzanine Loan Repaid in March 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	0	18,395
Total floating rate | Mezzanine Loan Repaid in February 2016 [Member]
Debt Investments Held [Abstract]
Future Funding Obligations	0
Senior Financing	0
Carrying Value	$ 0	$ 40,346

Debt and Preferred Equity Inv52

Debt and Preferred Equity Investments (Preferred Equity Investments)(Details)	12 Months Ended
	Dec. 31, 2016USD ($)segment	Dec. 31, 2015USD ($)segment	Dec. 31, 2014USD ($)
Preferred Equity Investments [Line Items]
Interest rate (as a percent)	9.34%
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of year	$ 0	$ 0	$ 1,000,000
Expensed	0	0	0
Recoveries	0	0	0
Charge-offs and reclassifications	0	0	(1,000,000)
Balance at end of period	$ 0	$ 0	$ 0
Number of portfolio segments of financial receivables (segment) | segment	1	1
Additional amount of financing receivables included in other assets	$ 144,500,000	$ 168,300,000
Preferred Equity Investments
Preferred Equity Investments [Line Items]
Interest rate (as a percent)	8.16%
Future Funding Obligations	$ 0
Senior Financing	130,272,000
Carrying Value	47,875,000	42,176,000
Preferred Equity, March 2018
Preferred Equity Investments [Line Items]
Future Funding Obligations	0
Senior Financing	71,486,000
Carrying Value	9,982,000	9,967,000
Preferred Equity, November 2018
Preferred Equity Investments [Line Items]
Future Funding Obligations	0
Senior Financing	58,786,000
Carrying Value	37,893,000	$ 32,209,000
Junior Mortgage Participation Acquired in September 2014 [Member]
Preferred Equity Investments [Line Items]
Carrying Value	$ 0

Investments in Unconsolidated53

Investments in Unconsolidated Joint Ventures (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016USD ($)ft²	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)ft²note	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Schedule of Equity Method Investments [Line Items]
Approximate Square Feet (sqft) | ft²	12,539,646								12,539,646
Loans Receivable, Gross, Commercial, Acquisition	$ 124,542				$ 99,936				$ 124,542	$ 99,936
Total mortgages and other loans payable	684,642				753,424				684,642	753,424
Total joint venture mortgages and other loans payable	676,068				745,728				676,068	745,728
Deferred financing costs, net	(22,800)				(25,200)				(22,800)	(25,200)
Commercial real estate property, net	6,071,648				6,160,645				6,071,648	6,160,645
Debt, preferred equity and other investments, net of discounts and deferred origination fees of $16,705 and $18,759 in 2016 and 2015, respectively	1,640,412				1,670,020				1,640,412	1,670,020
Other assets	374,091				355,566				374,091	355,566
Other liabilities	160,982				116,088				160,982	116,088
Company's investments in unconsolidated joint ventures	174,127				100,192				174,127	100,192
Operating expenses									166,137	163,969	$ 154,374
Real estate taxes									152,010	143,873	133,567
Amortization of deferred financing costs									7,918	7,519	7,810
Depreciation and amortization									212,514	202,474	196,505
Total expenses									669,716	661,453	646,524
Equity in net income from unconsolidated joint ventures	$ 4,110	$ 4,276	$ 3,666	$ 2,457	2,265	$ 2,296	$ 2,153	$ 2,127	$ 14,509	8,841	4,491
131-137 Spring Street
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	20.00%								20.00%
Economic Interest (as a percent)	20.00%								20.00%
Approximate Square Feet (sqft) | ft²	68,342								68,342
Equity Method Investment, Aggregate Cost	$ 277,750								$ 277,750
76 11th Avenue [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	33.33%								33.33%
Economic Interest (as a percent)	35.09%								35.09%
Approximate Square Feet (sqft) | ft²	764,000								764,000
Equity Method Investment, Aggregate Cost	$ 138,240								$ 138,240
Exit Fee, Percentage Owned									50.00%
Corporate Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Total joint venture mortgages and other loans payable	141,000				141,000				$ 141,000	141,000
Deferred financing costs, net	(3,970)				(5,077)				(3,970)	(5,077)
Total joint venture mortgages and other loans payable, net	137,030				135,923				137,030	135,923
Commercial real estate property, net	279,451				285,689				279,451	285,689
Debt, preferred equity and other investments, net of discounts and deferred origination fees of $16,705 and $18,759 in 2016 and 2015, respectively	273,749				99,936				273,749	99,936
Other assets	18,922				16,897				18,922	16,897
Total assets	572,122				402,522				572,122	402,522
Mortgages and other loans payable, net	137,030				135,923				137,030	135,923
Other liabilities	22,185				25,462				22,185	25,462
Members' equity	412,907				241,137				412,907	241,137
Total liabilities and members' equity	572,122				402,522				572,122	402,522
Total revenues									38,524	19,855	7,121
Operating expenses									1,238	1,686	59
Real estate taxes									1,192	1,262	0
Interest expense, net of interest income									2,895	1,070	0
Amortization of deferred financing costs									1,108	462	0
Transaction related costs									0	5,262	181
Depreciation and amortization									8,404	3,207	0
Total expenses									14,837	12,949	240
Net income									23,687	6,906	6,881
Equity in net income from unconsolidated joint ventures									14,509	8,841	$ 4,491
Corporate Joint Venture [Member] | 131-137 Spring Street
Schedule of Equity Method Investments [Line Items]
Total mortgages and other loans payable	141,000				141,000				$ 141,000	141,000
Corporate Joint Venture [Member] | 76 11th Avenue [Member]
Schedule of Equity Method Investments [Line Items]
Exit Fee, Percentage Owned									38.00%
General Partner's Capital Class A Common Units | Corporate Joint Venture [Member] | 76 11th Avenue [Member]
Schedule of Equity Method Investments [Line Items]
Number of Mezzanine Notes Secured | note									2
Exit Fee, Percentage Owned									25.00%
Extension Fee, Percentage Owned									31.00%
Participating Financing Due March 2017 [Member]
Schedule of Equity Method Investments [Line Items]
Loans Receivable, Gross, Commercial, Acquisition	100,000				99,936				$ 100,000	99,936
Mezzanine Loan Due July 2036 [Member]
Schedule of Equity Method Investments [Line Items]
Loans Receivable, Gross, Commercial, Acquisition	$ 24,542				$ 0				$ 24,542	$ 0
Weighted Average | Corporate Joint Venture [Member] | 131-137 Spring Street
Schedule of Equity Method Investments [Line Items]
Interest Rate (as a percent)	2.03%								2.03%

Mortgages and Other Loans Pay54

Mortgages and Other Loans Payable (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Mortgage note and other loan payable
Total mortgages and other loans payable	$ 684,642,000	$ 753,424,000
Secured Debt, Deferred Finance Costs, Net	(8,574,000)	(7,696,000)
Total fixed and floating rate debt	676,068,000	745,728,000
Collateral Already Posted, Aggregate Fair Value	1,700,000,000	2,000,000,000
Master Repurchase Agreement
Mortgage note and other loan payable
Total mortgages and other loans payable	184,642,000	253,424,000
Maximum borrowing capacity	$ 300,000,000
Basis Point Fee (as a percent)	0.25%
Threshold amount for basis point fee to be applicable (less than)	$ 150,000,000
919 Third Avenue
Mortgage note and other loan payable
Total fixed rate debt	$ 500,000,000	$ 500,000,000
919 Third Ave
Mortgage note and other loan payable
Controlling interest in the joint venture (as a percent)	51.00%
Weighted Average | Master Repurchase Agreement
Mortgage note and other loan payable
Interest Rate (as a percent)	3.04%
Weighted Average | 919 Third Avenue
Mortgage note and other loan payable
Interest rate (as a percent)	5.12%
LIBOR | Minimum | Master Repurchase Agreement
Mortgage note and other loan payable
Interest rate (as a percent)	2.25%
LIBOR | Maximum | Master Repurchase Agreement
Mortgage note and other loan payable
Interest rate (as a percent)	4.00%

Corporate Indebtedness (Details

Corporate Indebtedness (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Corporate Indebtedness
Revolving credit facility, net	$ 0	$ 985,055,000
Debt disclosures by scheduled maturity date
Deferred financing costs, net	(22,800,000)	(25,200,000)
Scheduled amortization and principal repayments
2,017	0
2,018	434,642,000
2,019	1,183,000,000
2,020	250,000,000
2,021	0
Thereafter	800,000,000
Total amortization of debt and principal repayments	2,667,642,000
Interest expense
Interest expense before capitalized interest	110,393,000	120,467,000	$ 133,180,000
Interest capitalized	(1,171,000)	(1,107,000)	(3,753,000)
Interest income	(14,000)	(18,000)	(71,000)
Interest expense, net	109,208,000	119,342,000	$ 129,356,000
Revolving credit facility
Corporate Indebtedness
Maximum borrowing capacity	1,600,000,000
Maximum borrowing capacity, optional expansion	3,000,000,000
Revolving credit facility, net	$ 0
Debt disclosures by scheduled maturity date
Effective Rate (as a percent)	1.78%
Scheduled amortization and principal repayments
2,017	$ 0
2,018	0
2,019	0
2,020	0
2,021	0
Thereafter	0
Total amortization of debt and principal repayments	$ 0
Revolving credit facility | Minimum
Corporate Indebtedness
Facility fee on total commitments (as a percent)	0.125%
Facility fee on total commitments, payable quarterly in arrears (as a percent)	0.25%
Revolving credit facility | Maximum
Corporate Indebtedness
Facility fee on total commitments (as a percent)	0.30%
Term loan
Corporate Indebtedness
Maximum borrowing capacity	$ 1,183,000,000
Debt disclosures by scheduled maturity date
Effective Rate (as a percent)	1.96%
Scheduled amortization and principal repayments
2,017	$ 0
2,018	0
2,019	1,183,000,000
2,020	0
2,021	0
Thereafter	0
Total amortization of debt and principal repayments	1,183,000,000
Credit Facility 2012
Corporate Indebtedness
Letters of credit	56,500,000
Ability to borrow under line of credit facility	1,500,000,000
Mortgage and Other Loans Payable
Scheduled Amortization
2,017	0
2,018	0
2,019	0
2,020	0
2,021	0
Thereafter	0
Total amortization of debt	0
Principal Repayments
2,017	0
2,018	184,642,000
2,019	0
2,020	0
2,021	0
Thereafter	500,000,000
Total principal repayments	684,642,000
Senior Unsecured Notes
Scheduled amortization and principal repayments
2,017	0
2,018	250,000,000
2,019	0
2,020	250,000,000
2,021	0
Thereafter	300,000,000
Total amortization of debt and principal repayments	800,000,000
Line of Credit [Member] | Term loan
Scheduled amortization and principal repayments
Total amortization of debt and principal repayments	1,200,000,000	929,500,000
Line of Credit [Member] | Credit Facility 2012
Scheduled amortization and principal repayments
Total amortization of debt and principal repayments	(6,300,000)	985,100,000
Senior Unsecured Notes
Debt disclosures by scheduled maturity date
Unpaid Principal Balance	800,000,000
Accreted Balance	799,880,000	1,055,106,000
Deferred financing costs, net	(4,620,000)	(5,303,000)
Senior Notes, Net of Deferred Finance Costs	795,260,000	1,049,803,000
Senior Unsecured Notes | 5.00% senior unsecured notes maturing on August 15, 2018
Debt disclosures by scheduled maturity date
Unpaid Principal Balance	250,000,000
Accreted Balance	$ 249,880,000	249,810,000
Coupon Rate (as a percent)	5.00%
Effective Rate (as a percent)	5.00%
Term (in Years)	7 years
Senior Unsecured Notes | 7.75% senior unsecured notes maturing on March 15, 2020
Debt disclosures by scheduled maturity date
Unpaid Principal Balance	$ 250,000,000
Accreted Balance	$ 250,000,000	250,000,000
Coupon Rate (as a percent)	7.75%
Effective Rate (as a percent)	7.75%
Term (in Years)	10 years
Senior Unsecured Notes | 4.50% senior unsecured notes maturing on December 01, 2022
Debt disclosures by scheduled maturity date
Unpaid Principal Balance	$ 200,000,000
Accreted Balance	$ 200,000,000	200,000,000
Coupon Rate (as a percent)	4.50%
Effective Rate (as a percent)	4.50%
Term (in Years)	10 years
Senior Unsecured Notes | 4.27% senior unsecured notes maturing on December 17, 2025
Debt disclosures by scheduled maturity date
Unpaid Principal Balance	$ 100,000,000
Accreted Balance	$ 100,000,000	100,000,000
Coupon Rate (as a percent)	4.27%
Effective Rate (as a percent)	4.27%
Term (in Years)	10 years
Senior Unsecured Notes | 4.00% senior unsecured notes redeemed in April 2015
Debt disclosures by scheduled maturity date
Unpaid Principal Balance	$ 0
Accreted Balance	$ 0	$ 255,296,000
Senior Unsecured Notes | 3.00% exchangeable senior notes due 2017
Debt disclosures by scheduled maturity date
Coupon Rate (as a percent)	3.00%
LIBOR | Revolving credit facility
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.25%
LIBOR | Revolving credit facility | Minimum
Corporate Indebtedness
Interest rate added to base rate (as a percent)	0.875%
LIBOR | Revolving credit facility | Maximum
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.55%
LIBOR | Term loan
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.40%
LIBOR | Term loan | Minimum
Corporate Indebtedness
Interest rate added to base rate (as a percent)	0.95%
LIBOR | Term loan | Maximum
Corporate Indebtedness
Interest rate added to base rate (as a percent)	1.90%

Preferred Units (Details)

Preferred Units (Details)	12 Months Ended
	Dec. 31, 2016USD ($)$ / sharesshares	Aug. 31, 2015shares	Jul. 22, 2015USD ($)
Class of Stock [Line Items]
Number of company common stock issued on conversion of Series B preferred units	6.71348
Series A Preferred Units
Class of Stock [Line Items]
Fair value of embedded derivative liability | $	$ 0		$ 0
Partnership Interest | Series A Preferred Units
Class of Stock [Line Items]
Shares of common stock reserved for issuance upon redemption of units of limited partnership interest in operating partnership (shares)	109,161
Dividend rate preferred units (as a percent)	3.50%
Liquidation preference of preferred units (in dollars per share) | $ / shares	$ 1,000
Number of preferred units issued (in shares)		109,161
Annual dividends on preferred units (in dollars per share) | $ / shares	$ 35
Partnership Interest | Series B Preferred Units
Class of Stock [Line Items]
Number of preferred units issued (in shares)	0

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value of Financial Instruments
Debt, preferred equity and other investments, net of discounts and deferred origination fees of $16,705 and $18,759 in 2016 and 2015, respectively	$ 1,640,412	$ 1,670,020
Company's investments in unconsolidated joint ventures	174,127	100,192
Other investments	144,500	168,300
Carrying Value
Fair Value of Financial Instruments
Debt, preferred equity and other investments, net of discounts and deferred origination fees of $16,705 and $18,759 in 2016 and 2015, respectively	1,640,412	1,670,020
Fixed rate debt	2,099,880	1,585,106
Variable rate debt	567,642	2,150,424
Total	2,667,522	3,735,530
Fair Value | Level 3
Fair Value of Financial Instruments
Fixed rate debt	2,183,042	1,663,078
Variable rate debt	580,083	2,164,673
Total	2,763,125	3,827,751
Minimum | Fair Value
Fair Value of Financial Instruments
Mortgage Loans on Real Estate, Fair Value, Low End of Range	1,600,000	1,700,000
Maximum | Fair Value
Fair Value of Financial Instruments
Mortgage Loans on Real Estate Fair Value, High End of Range	$ 1,800,000	$ 1,800,000

Financial Instruments_ Deriva58

Financial Instruments: Derivatives and Hedging (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Loss from settlement of hedges included in accumulated other comprehensive loss	$ 1,600	$ 2,000
Estimated current balance held in accumulated other comprehensive loss to be reclassified into earnings within the next 12 months	400
Amount of Loss Recognized in Other Comprehensive Loss (Effective Portion)	(13)	(109)	$ (135)
Amount of Gain Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion)	611	999	970
Amount of Gain Recognized into Income (Ineffective Portion)	$ 3	$ 3	$ 4

Rental Income (Details)

Rental Income (Details) - Consolidated Properties $ in Thousands	Dec. 31, 2016USD ($)
Approximate future minimum rents to be received over the next five years and thereafter for non-cancelable operating leases
2,017	$ 622,264
2,018	602,291
2,019	567,694
2,020	501,107
2,021	447,588
Thereafter	2,173,526
Total minimum lease payments	$ 4,914,470

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jul. 22, 2015
Related Party Transactions
Related party receivable	$ 0	$ 90,000
Affiliate
Related Party Transactions
Profit participation received from related party	3,300	3,300	$ 3,300
Alliance Building Services
Related Party Transactions
Payments made for services	8,100	9,900	9,100
SL Green
Related Party Transactions
Allocation of salary and other operating costs from related party	11,500	10,400	9,800
Insurance expense incurred	$ 5,900	$ 6,600	$ 6,400
SL Green | Notes receivable | Promissory Note due July 22, 2017
Related Party Transactions
Related party receivable				$ 90,000
Interest rate (as a percent)				6.00%

Benefit Plans Benefit Plans (Na

Benefit Plans Benefit Plans (Narrative)(Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Multi-employer plans
Plan contributions from all employers	$ 9,487		$ 9,676		$ 9,295
Health Plan
Multi-employer plans
Plan contributions from all employers		$ 1,200,000		$ 1,100,000		$ 1,000,000
Contributions by company (less than)	5.00%
Pension Plan
Multi-employer plans
Surcharge	No
Plan contributions from all employers		$ 249,500		$ 221,900		$ 226,700

Benefit Plans (Details)

Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Multi-employer plans
Plan contributions	$ 9,487	$ 9,676	$ 9,295
Health Plan
Multi-employer plans
Plan contributions	6,366	4,843	4,585
Other plans
Multi-employer plans
Plan contributions	902	3,300	3,181
Pension Plan
Multi-employer plans
Plan contributions	$ 2,219	$ 1,533	$ 1,529

Commitments and Contingencies63

Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)extenstion_option
Other Commitments [Line Items]
Minimum initial term of noncancellable operating leases (in years)	1 year
Non-cancellable operating leases
2,017	$ 20,586
2,018	20,586
2,019	20,586
2,020	20,586
2,021	20,736
Thereafter	308,202
Total minimum lease payments	$ 411,282
711 Third Avenue
Other Commitments [Line Items]
Percentage of the fee not owned by the entity	50.00%
711 Third Avenue | Through July 2016
Other Commitments [Line Items]
Required annual ground lease payments	$ 5,300
711 Third Avenue | After July 2016
Other Commitments [Line Items]
Required annual ground lease payments	5,500
461 Fifth Avenue
Other Commitments [Line Items]
Required annual ground lease payments	$ 2,100
Number of renewal options available | extenstion_option	3
Term of second renewal option (in years)	21 years
Term of third renewal option (in years)	15 years
625 Madison Avenue
Other Commitments [Line Items]
Required annual ground lease payments	$ 4,600
Number of renewal options available | extenstion_option	2
Term of second renewal option (in years)	23 years
1185 Avenue of the Americas
Other Commitments [Line Items]
Required annual ground lease payments	$ 6,900
Number of renewal options available | extenstion_option	1
Term of first renewal option (in years)	23 years
919 Third Avenue
Other Commitments [Line Items]
Required annual ground lease payments	$ 900
1055 Washington Boulevard
Other Commitments [Line Items]
Required annual ground lease payments	600
Secured Debt [Member] | Federal Home Loan Bank of New York (FHLBNY) [Member]
Other Commitments [Line Items]
Line of Credit Facility, Collateral Fees, Amount	$ 4,800

Quarterly Financial Data of t64

Quarterly Financial Data of the Company (unaudited) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 232,658	$ 271,336	$ 231,758	$ 239,664	$ 238,283	$ 237,651	$ 234,631	$ 214,668	$ 975,416	$ 925,233	$ 847,522
Income from continuing operations before equity in net income from unconsolidated joint ventures, (loss) gain on sale of real estate, depreciable real estate reserves, unrealized gain (loss) on embedded derivative and loss on extinguishment of debt	66,056	98,647	71,254	69,743	69,152	65,541	76,236	52,851	305,700	263,780	200,998
Equity in net income from unconsolidated joint ventures	4,110	4,276	3,666	2,457	2,265	2,296	2,153	2,127	14,509	8,841	4,491
Loss on sale of real estate	(10)	0	(6,899)	0	(879)	101,069	0	0	(6,909)	100,190	0
Depreciable real estate reserves					0	(9,998)	0	0	0	(9,998)	0
Unrealized gain (loss) on embedded derivative					1,800	(1,800)	0	0
Loss on extinguishment of debt					0	0	0	(49)	0	(49)	(7,385)
Net income	70,156	102,923	68,021	72,200	72,338	157,108	78,389	54,929	313,300	362,764	403,238
Net income attributable to noncontrolling interests in other partnerships	(1,071)	(1,279)	(2,062)	(12)	(1,946)	(293)	(6,380)	(550)	(4,424)	(9,169)	(2,641)
Preferred units dividend	(956)	(955)	(955)	(955)	(955)	(743)	0	0	(3,821)	(1,698)	0
Net income attributable to ROP common unitholder	$ 68,129	$ 100,689	$ 65,004	$ 71,233	$ 69,437	$ 156,072	$ 72,009	$ 54,379	$ 305,055	$ 351,897	$ 400,597

Segment Information (Details)

Segment Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)segment	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Segment information
Number of reportable segments | segment									2
Total revenues	$ 232,658	$ 271,336	$ 231,758	$ 239,664	$ 238,283	$ 237,651	$ 234,631	$ 214,668	$ 975,416	$ 925,233	$ 847,522
Income from continuing operations before equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, depreciable real estate reserves, and loss on early extinguishment of debt.									320,209	272,621	205,489
Total assets	8,754,613				8,833,317				8,754,613	8,833,317
Equity in net gain on sale of interest in unconsolidated joint venture									0	0	85,559
(Loss) gain on sale of real estate	(10)	0	(6,899)	0	(879)	101,069	0	0	(6,909)	100,190	0
Depreciable real estate reserves					0	(9,998)	0	0	0	(9,998)	0
Loss on early extinguishment of debt					0	0	0	(49)	0	(49)	(7,385)
Income from continuing operations									313,300	362,764	283,663
Net income from discontinued operations									0	0	1,996
Gain on sale of discontinued operations									0	0	117,579
Net income	70,156	$ 102,923	$ 68,021	$ 72,200	72,338	$ 157,108	$ 78,389	$ 54,929	313,300	362,764	403,238
Operating Segments | Real Estate Segment
Segment information
Total revenues									750,233	721,697	647,555
Income from continuing operations before equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, depreciable real estate reserves, and loss on early extinguishment of debt.									118,199	96,821	34,821
Total assets	6,786,479				6,791,377				6,786,479	6,791,377
Operating Segments | Debt and Preferred Equity Segment
Segment information
Total revenues									225,183	203,536	199,967
Income from continuing operations before equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, depreciable real estate reserves, and loss on early extinguishment of debt.									202,010	175,800	$ 170,668
Total assets	$ 1,968,134				$ 2,041,940				$ 1,968,134	$ 2,041,940

Schedule II - Valuation and Q66

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Tenant and other receivables—allowance
Changes in valuation allowance
Balance at Beginning of Year	$ 5,593	$ 5,820	$ 5,382
Additions Charged Against Operations/Recovery	3,604	4,363	5,635
Uncollectible Accounts Written-off	(4,318)	(4,590)	(5,197)
Balance at End of Year	4,879	5,593	5,820
Deferred rent receivable—allowance
Changes in valuation allowance
Balance at Beginning of Year	14,788	17,745	18,829
Additions Charged Against Operations/Recovery	3,955	1,775	2,916
Uncollectible Accounts Written-off	(945)	(4,732)	(4,000)
Balance at End of Year	$ 17,798	$ 14,788	$ 17,745

Schedule III - Real Estate An67

Schedule III - Real Estate And Accumulated Depreciation (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Real Estate And Accumulated Depreciation
Encumbrances	$ 500,000
Initial Cost
Land	1,823,639
Building & Improvements	4,988,828
Cost Capitalized Subsequent To Acquisition
Land	(18,441)
Building & Improvements	714,844
Gross Amount at Which Carried at Close of Period
Land	1,805,198
Building & Improvements	5,703,672
Total	7,508,870	$ 7,428,243	$ 7,203,216	$ 6,670,210
Accumulated Depreciation	1,437,222	$ 1,267,598	$ 1,123,412	$ 983,273
810 Seventh Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	114,077
Building & Improvements	476,386
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	65,985
Gross Amount at Which Carried at Close of Period
Land	114,077
Building & Improvements	542,371
Total	656,448
Accumulated Depreciation	145,216
461 Fifth Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	0
Building & Improvements	62,695
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	10,723
Gross Amount at Which Carried at Close of Period
Land	0
Building & Improvements	73,418
Total	73,418
Accumulated Depreciation	26,105
750 Third Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	51,093
Building & Improvements	205,972
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	39,436
Gross Amount at Which Carried at Close of Period
Land	51,093
Building & Improvements	245,408
Total	296,501
Accumulated Depreciation	85,282
919 Third Avenue
Real Estate And Accumulated Depreciation
Encumbrances	500,000
Initial Cost
Land	223,529
Building & Improvements	1,033,198
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	38,714
Gross Amount at Which Carried at Close of Period
Land	223,529
Building & Improvements	1,071,912
Total	1,295,441
Accumulated Depreciation	$ 274,778
Interest in property (as a percent)	51.00%
555 W. 57th Street
Real Estate And Accumulated Depreciation
Encumbrances	$ 0
Initial Cost
Land	18,846
Building & Improvements	78,704
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	59,564
Gross Amount at Which Carried at Close of Period
Land	18,846
Building & Improvements	138,268
Total	157,114
Accumulated Depreciation	58,187
1185 Avenue of the Americas
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	0
Building & Improvements	728,213
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	39,403
Gross Amount at Which Carried at Close of Period
Land	0
Building & Improvements	767,616
Total	767,616
Accumulated Depreciation	221,415
1350 Avenue of the Americas
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	91,038
Building & Improvements	380,744
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	37,736
Gross Amount at Which Carried at Close of Period
Land	91,038
Building & Improvements	418,480
Total	509,518
Accumulated Depreciation	114,264
1100 King Street - 1-6 International Drive
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	49,392
Building & Improvements	104,376
Cost Capitalized Subsequent To Acquisition
Land	(24,004)
Building & Improvements	23,954
Gross Amount at Which Carried at Close of Period
Land	25,388
Building & Improvements	128,330
Total	153,718
Accumulated Depreciation	35,062
520 White Plains Road
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	6,324
Building & Improvements	26,096
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	6,602
Gross Amount at Which Carried at Close of Period
Land	6,324
Building & Improvements	32,698
Total	39,022
Accumulated Depreciation	9,158
115-117 Stevens Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	5,933
Building & Improvements	23,826
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	5,390
Gross Amount at Which Carried at Close of Period
Land	5,933
Building & Improvements	29,216
Total	35,149
Accumulated Depreciation	7,622
100 Summit Lake Drive
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	10,526
Building & Improvements	43,109
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	8,476
Gross Amount at Which Carried at Close of Period
Land	10,526
Building & Improvements	51,585
Total	62,111
Accumulated Depreciation	15,149
200 Summit Lake Drive
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	11,183
Building & Improvements	47,906
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	10,448
Gross Amount at Which Carried at Close of Period
Land	11,183
Building & Improvements	58,354
Total	69,537
Accumulated Depreciation	16,543
500 Summit Lake Drive
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	9,777
Building & Improvements	39,048
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	5,290
Gross Amount at Which Carried at Close of Period
Land	9,777
Building & Improvements	44,338
Total	54,115
Accumulated Depreciation	11,672
360 Hamilton Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	29,497
Building & Improvements	118,250
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	13,844
Gross Amount at Which Carried at Close of Period
Land	29,497
Building & Improvements	132,094
Total	161,591
Accumulated Depreciation	35,784
680 Washington Boulevard
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	11,696
Building & Improvements	45,364
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	10,126
Gross Amount at Which Carried at Close of Period
Land	11,696
Building & Improvements	55,490
Total	67,186
Accumulated Depreciation	$ 14,462
Interest in property (as a percent)	51.00%
750 Washington Boulevard
Real Estate And Accumulated Depreciation
Encumbrances	$ 0
Initial Cost
Land	16,916
Building & Improvements	68,849
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	8,350
Gross Amount at Which Carried at Close of Period
Land	16,916
Building & Improvements	77,199
Total	94,115
Accumulated Depreciation	$ 19,727
Interest in property (as a percent)	51.00%
1010 Washington Boulevard
Real Estate And Accumulated Depreciation
Encumbrances	$ 0
Initial Cost
Land	7,747
Building & Improvements	30,423
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	6,598
Gross Amount at Which Carried at Close of Period
Land	7,747
Building & Improvements	37,021
Total	44,768
Accumulated Depreciation	9,722
1055 Washington Boulevard
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	13,516
Building & Improvements	53,228
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	7,559
Gross Amount at Which Carried at Close of Period
Land	13,516
Building & Improvements	60,787
Total	74,303
Accumulated Depreciation	15,655
400 Summit Lake Drive
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	38,889
Building & Improvements	1
Cost Capitalized Subsequent To Acquisition
Land	285
Building & Improvements	2
Gross Amount at Which Carried at Close of Period
Land	39,174
Building & Improvements	3
Total	39,177
Accumulated Depreciation	0
609 Fifth Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	36,677
Building & Improvements	145,954
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	8,270
Gross Amount at Which Carried at Close of Period
Land	36,677
Building & Improvements	154,224
Total	190,901
Accumulated Depreciation	41,993
110 East 42nd Street
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	34,000
Building & Improvements	46,411
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	18,337
Gross Amount at Which Carried at Close of Period
Land	34,000
Building & Improvements	64,748
Total	98,748
Accumulated Depreciation	15,000
304 Park Avenue South
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	54,189
Building & Improvements	75,619
Cost Capitalized Subsequent To Acquisition
Land	300
Building & Improvements	11,792
Gross Amount at Which Carried at Close of Period
Land	54,489
Building & Improvements	87,411
Total	141,900
Accumulated Depreciation	13,322
635 Sixth Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	24,180
Building & Improvements	37,158
Cost Capitalized Subsequent To Acquisition
Land	163
Building & Improvements	50,189
Gross Amount at Which Carried at Close of Period
Land	24,343
Building & Improvements	87,347
Total	111,690
Accumulated Depreciation	4,428
641 Sixth Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	45,668
Building & Improvements	67,316
Cost Capitalized Subsequent To Acquisition
Land	308
Building & Improvements	3,076
Gross Amount at Which Carried at Close of Period
Land	45,976
Building & Improvements	70,392
Total	116,368
Accumulated Depreciation	9,339
315 West 33rd Street
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	195,834
Building & Improvements	164,429
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	8,919
Gross Amount at Which Carried at Close of Period
Land	195,834
Building & Improvements	173,348
Total	369,182
Accumulated Depreciation	15,160
16 Court Street
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	19,217
Building & Improvements	63,210
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	16,092
Gross Amount at Which Carried at Close of Period
Land	19,217
Building & Improvements	79,302
Total	98,519
Accumulated Depreciation	10,366
125 Chubb Way
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	5,884
Building & Improvements	25,958
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	25,556
Gross Amount at Which Carried at Close of Period
Land	5,884
Building & Improvements	51,514
Total	57,398
Accumulated Depreciation	9,170
Williamsburg
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	3,677
Building & Improvements	14,708
Cost Capitalized Subsequent To Acquisition
Land	2,523
Building & Improvements	(4,550)
Gross Amount at Which Carried at Close of Period
Land	6,200
Building & Improvements	10,158
Total	16,358
Accumulated Depreciation	1,604
115 Spring Street
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	11,078
Building & Improvements	44,799
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	1,686
Gross Amount at Which Carried at Close of Period
Land	11,078
Building & Improvements	46,485
Total	57,563
Accumulated Depreciation	2,918
635 Madison Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	205,632
Building & Improvements	15,805
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	0
Gross Amount at Which Carried at Close of Period
Land	205,632
Building & Improvements	15,805
Total	221,437
Accumulated Depreciation	910
125 Park Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	120,900
Building & Improvements	189,714
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	68,264
Gross Amount at Which Carried at Close of Period
Land	120,900
Building & Improvements	257,978
Total	378,878
Accumulated Depreciation	54,736
625 Madison Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	0
Building & Improvements	246,673
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	41,937
Gross Amount at Which Carried at Close of Period
Land	0
Building & Improvements	288,610
Total	288,610
Accumulated Depreciation	97,690
102 Greene Street
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	8,215
Building & Improvements	26,717
Cost Capitalized Subsequent To Acquisition
Land	35
Building & Improvements	482
Gross Amount at Which Carried at Close of Period
Land	8,250
Building & Improvements	27,199
Total	35,449
Accumulated Depreciation	888
711 Third Avenue
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	19,844
Building & Improvements	42,499
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	57,916
Gross Amount at Which Carried at Close of Period
Land	19,844
Building & Improvements	100,415
Total	120,259
Accumulated Depreciation	$ 34,418
Interest in property (as a percent)	50.00%
752 Madison Avenue
Real Estate And Accumulated Depreciation
Encumbrances	$ 0
Initial Cost
Land	282,415
Building & Improvements	0
Cost Capitalized Subsequent To Acquisition
Land	1,871
Building & Improvements	0
Gross Amount at Which Carried at Close of Period
Land	284,286
Building & Improvements	0
Total	284,286
Accumulated Depreciation	0
110 Greene Street
Real Estate And Accumulated Depreciation
Encumbrances	0
Initial Cost
Land	45,120
Building & Improvements	215,470
Cost Capitalized Subsequent To Acquisition
Land	0
Building & Improvements	3,985
Gross Amount at Which Carried at Close of Period
Land	45,120
Building & Improvements	219,455
Total	264,575
Accumulated Depreciation	$ 9,459
Interest in property (as a percent)	90.00%
Other
Real Estate And Accumulated Depreciation
Encumbrances	$ 0
Initial Cost
Land	1,130
Building & Improvements	0
Cost Capitalized Subsequent To Acquisition
Land	78
Building & Improvements	4,693
Gross Amount at Which Carried at Close of Period
Land	1,208
Building & Improvements	4,693
Total	5,901
Accumulated Depreciation	$ 18

Schedule III - Real Estate An68

Schedule III - Real Estate And Accumulated Depreciation (Changes in Real Estate and Accumulated Depreciation)(Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Changes in real estate
Balance at beginning of year	$ 7,428,243	$ 7,203,216	$ 6,670,210
Acquisitions	0	329,996	491,023
Improvements	123,173	93,439	102,530
Retirements/disposals	(42,546)	(198,408)	(60,547)
Balance at end of year	7,508,870	7,428,243	7,203,216
Aggregate cost of land, buildings and improvements, before depreciation, for Federal income tax purposes	4,900,000
Changes in accumulated depreciation, exclusive of amounts relating to equipment, autos, and furniture and fixtures
Balance at beginning of year	1,267,598	1,123,412	983,273
Depreciation for year	183,873	175,039	165,840
Retirements/disposals	(14,249)	(30,853)	(25,701)
Balance at end of year	$ 1,437,222	$ 1,267,598	$ 1,123,412