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Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Operating Activities |  |  |
Net income/(loss) | $ 357,159 | $ 159,842 | $ 46,282
Adjustments to reconcile net income/(loss) to net cash provided by operating activities: |  |  |
Deprecation and amortization | 381,277 | 363,929 | 348,231
(Gain)/loss on the sale of real estate, net of tax | 251,677 | 143,647 | 41,919
Impairment loss, net of tax | 0 | 0 | 1,470
Tax benefit/(provision), net | (3,886) | (15,136) | (7,299)
(Income)/loss from unconsolidated entities | (62,329) | 7,006 | 415
Amortization of share-based compensation | 18,017 | 13,954 | 9,531
Other | 6,612 | 13,104 | 15,025
Changes in operating assets and liabilities: |  |  |
Increase/(decrease) in operating assets | (3,968) | (1,074) | (15,135)
Increase/(decrease) in operating liabilites | (9,590) | (5,618) | (16,699)
Net cash provided by operating activities | 431,615 | 392,360 | 339,902
Investing Activities |  |  |
Acquisition of real estate assets (net of liabilities assumed) and initial capital expenditures | (244,769) | (228,810) | 0
Proceeds from sales of real estate investments, net | 387,650 | 383,886 | 250,043
Development of real estate assets | (103,205) | (251,493) | (280,603)
Capital expenditures and other major improvements - real estate assets, net of escrow reimbursement | (113,400) | (96,679) | (153,676)
Capital expenditures - non-real estate assets | (4,049) | (5,497) | (7,639)
Investment in unconsolidated joint ventures | (217,642) | (222,930) | (43,291)
Distributions received from unconsolidated joint venture | 59,291 | 59,199 | 130,984
(Issuance)/repayment of notes receivable | (2,325) | 68,664 | (19,027)
Net cash provided by/(used in) investing activities | (238,449) | (293,660) | (123,209)
Financing Activities |  |  |
Payments on secured debt | (193,958) | (80,961) | (46,564)
Proceeds from the issuance of secured debt | 127,600 | 5,502 | 0
Payments on unsecured debt | (325,540) | (312,500) | (122,500)
Proceeds from the issuance of unsecured debt | 299,310 | 298,956 | 299,943
Net proceeds/(repayment) of revolving bank debt | (2,500) | 152,500 | (76,000)
Proceeds from the issuance of common shares through public offering, net | 210,011 | 99,849 | 0
Distributions paid to non-controlling interests | (10,654) | (9,929) | (9,348)
Distributions paid to preferred stockholders | (3,722) | (3,724) | (3,724)
Distributions paid to common stockholders | (283,168) | (256,100) | (231,822)
Other | (19,027) | (7,318) | (8,544)
Net cash (used in)/provided by financing activities | (201,648) | (113,725) | (198,559)
Net increase/(decrease) in cash and cash equivalents | (8,482) | (15,025) | 18,134
Cash and cash equivalents, beginning of period | 15,224 | 30,249 | 12,115
Cash and cash equivalents, end of period | 6,742 | 15,224 | 30,249
Supplemental Information: |  |  |
Interest paid during the period, net of amounts capitalized | 130,240 | 131,815 | 127,877
Non-cash transactions: |  |  |
Acquisition of communities in exchange for DownREIT units and assumption of debt | 660,832 | 0 | 0
Secured debt assumed in the acquisitions of properties, including asset exchange | 0 | 0 | 63,595
Fair Value Adjustment of Debt Assumed in Business Acquisition | 1,363 | 0 | 0
Real estate acquired in asset exchange or upon consolidation of joint ventures | 0 | 0 | 129,437
Real Estate Owned, Transfer to Real Estate Owned | 0 | 54,938 | 175,951
Development costs and capital expenditures incurred buy not yet paid | 20,375 | 34,746 | 37,220
Conversion of operating partnership non-controlling interests to common stock (112,174 shares in 2015; 153,451 shares in 2014; and 76,291 shares in 2013) 2011) | 3,817 | 4,372 | 1,817
Unconsolidated Joint Venture Vitruvian Park [Member] |  |  |
Adjustments to reconcile net income/(loss) to net cash provided by operating activities: |  |  |
(Income)/loss from unconsolidated entities | 3,711 | 4,068 | 2,851
1745 Shea [Member] |  |  |
Non-cash transactions: |  |  |
Secured debt assumed in the acquisitions of properties, including asset exchange | $ 24,067 | $ 0 | $ 0

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- Definition Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585 + Details
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- Definition Amount of cash outflow in the form of ordinary dividends to preferred shareholders of the parent entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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- Definition The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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- Definition The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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- Definition Payments to develop real estate assets is the process of adding improvements on or to a parcel of land. Such improvements may include drainage, utilities, subdividing, access, buildings, and any combination of these elements; and are generally classified as cash flow from investing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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- Definition The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585 + Details
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- Definition The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3095-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3098-108585 + Details
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- Definition The net cash inflow or outflow in other borrowings not otherwise defined in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The cash inflow associated with the proceeds from sale of notes receivable, as well as principal collections from a borrowing supported by a written promise to pay an obligation (note receivable). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585 + Details
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569616-111683 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591552-111686 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591551-111686 + Details
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- Definition The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585 + Details
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- Definition Value of stock issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29-31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
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