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Real Estate Archstone Acquisition (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) property shares | Dec. 31, 2014 USD ($) property shares | Dec. 31, 2013 USD ($) $ / shares shares | Dec. 31, 2012 USD ($) $ / shares shares | Feb. 27, 2013 USD ($)
Properties acquired | property | 4 | 6 |  |  |
Property Units Acquired | 625 | 1,353 |  |  |
Master Leased Properties Acquired | 3 |  |  |  |
Payments to Acquire Businesses, Net of Cash Acquired | $ 0 | $ 0 | $ 4,000,875,000 |  |
Secured Debt | $ 4,704,870,000 | $ 5,086,515,000 |  |  |
Stock Issued During Period, Shares, New Issues | shares | 0 | 0 | 34,468,085 |  |
Number Of Operating Properties Under Long Term Ground Leases | 14 |  |  |  |
Land | $ 5,864,046,000 | $ 6,295,404,000 |  |  |
Depreciable property Abstract |  |  |  |  |
Buildings and improvements | 16,336,829,000 | 17,974,337,000 |  |  |
Furniture, fixtures and equipment | 1,207,098,000 | 1,365,276,000 |  |  |
Finite-Lived Intangible Asset, Acquired-in-Place Leases | 483,160,000 | 511,891,000 |  |  |
Projects under development | 1,122,376,000 | 1,343,919,000 |  |  |
Land held for development | 168,843,000 | 184,556,000 |  |  |
Other assets | 422,027,000 | 383,754,000 |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other | (366,387,000) | (389,915,000) |  |  |
Business Combination, Acquisition Related Costs | 1,000,000 | 400,000 | $ 300,000 |  |
Payments of Financing Costs | 6,425,000 | 10,982,000 | 16,526,000 |  |
Income (Loss) from Equity Method Investments | (15,025,000) | 7,952,000 | 58,156,000 |  |
ERPOP [Member] |  |  |  |  |
Payments to Acquire Businesses, Net of Cash Acquired | 0 | 0 | 4,000,875,000 |  |
Secured Debt | 4,704,870,000 | 5,086,515,000 |  |  |
Land | 5,864,046,000 | 6,295,404,000 |  |  |
Depreciable property Abstract |  |  |  |  |
Projects under development | 1,122,376,000 | 1,343,919,000 |  |  |
Land held for development | 168,843,000 | 184,556,000 |  |  |
Other assets | 422,027,000 | 383,754,000 |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other | (366,387,000) | (389,915,000) |  |  |
Payments of Financing Costs | 6,425,000 | 10,982,000 | 16,526,000 |  |
Income (Loss) from Equity Method Investments | (15,025,000) | 7,952,000 | $ 58,156,000 |  |
Consolidated Properties [Member] |  |  |  |  |
Secured Debt | 343,429,000 |  |  |  |
Depreciable property Abstract |  |  |  |  |
Other assets | 26,567,000 |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other | (786,000) |  |  |  |
Income (Loss) from Equity Method Investments | 1,501,000 |  |  |  |
Unconsolidated Properties [Member] |  |  |  |  |
Secured Debt | 174,846,000 |  |  |  |
Depreciable property Abstract |  |  |  |  |
Other assets | 448,000 |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other | (347,000) |  |  |  |
Income (Loss) from Equity Method Investments | 0 |  |  |  |
Archstone Transaction [Member] |  |  |  |  |
Business Acquisition, Percentage of Voting Interests Acquired |  |  |  |  | 60.00%
Properties acquired |  |  | 71 |  |
Property Units Acquired |  |  | 20,160 |  |
Partially Owned Consolidated Properties Acquired |  |  | 1 |  |
Partially Owned Consolidated Units Acquired |  |  | 432 |  |
Partially Owned Unconsolidated Properties Acquired |  |  | 1 |  |
Partially Owned Unconsolidated Units Acquired |  |  | 336 |  |
Master Leased Properties Acquired |  |  | 3 |  |
Master Leased Units Acquired |  |  | 853 |  |
Uncompleted Development Properties Acquired |  |  | 4 |  |
Uncompleted Development Units Acquired |  |  | 964 |  |
Land parcels acquired |  |  | 14 |  |
Net assets acquired |  |  | $ 8,968,389,000 |  |
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual |  |  | 514,700,000 |  |
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual |  |  | 352,800,000 |  |
Payments to Acquire Businesses, Net of Cash Acquired |  |  | 4,000,000,000 |  |
Secured Debt |  |  | $ 2,000,000,000 |  |
Stock Issued During Period, Shares, New Issues | shares |  |  | 34,468,085 | 21,850,000 |
Stock Issued During Period, Value, New Issues |  |  | $ 1,900,000,000 | $ 1,200,000,000 |
Average Price Per Common Share Issued | $ / shares |  |  | $ 55.99 | $ 54.75 |
Noncash or Part Noncash Acquisition, Debt Assumed |  |  | $ 3,100,000,000 |  |
Mark-to-Market Debt Premiums |  |  | 127,900,000 |  |
Proceeds from Sale of Other Assets |  |  | $ 4,500,000,000 |  |
Number Of Operating Properties Under Long Term Ground Leases |  |  | 9 |  |
Land |  |  | $ 2,239,000,000 |  |
Depreciable property Abstract |  |  |  |  |
Buildings and improvements |  |  | 5,765,538,000 |  |
Furniture, fixtures and equipment |  |  | 61,470,000 |  |
Finite-Lived Intangible Asset, Acquired-in-Place Leases |  |  | 304,830,000 |  |
Projects under development |  |  | 36,583,000 |  |
Land held for development |  |  | 244,097,000 |  |
Business Combination Purchase Price Allocation Investments in Unconsolidated Entities |  |  | 230,608,000 |  |
Other assets |  |  | 195,260,000 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other |  |  | (108,997,000) |  |
Finite-Lived Intangible Asset, Off-market Lease, Favorable, Gross |  |  |  |  | $ 1,260,000
Off-market Lease, Unfavorable |  |  |  |  | 2,400,000
Business Combination, Acquisition Related Costs | 83,100,000 |  |  |  |
Payments of Financing Costs | 13,500,000 |  | 2,500,000 |  |
Merger Expenses | 69,600,000 |  | 19,900,000 |  |
Income (Loss) from Equity Method Investments | 2,700,000 | 4,300,000 | 54,000,000 |  |
Business Acquisition, Pro Forma Revenue |  |  | 2,485,438,000 |  |
Business Acquisition, Proforma Income Loss From Continuing Operations |  |  | 203,286,000 |  |
Business Acquisition, Proforma Income Loss From Discontinued Operations Net Of Tax |  |  | 2,074,072,000 |  |
Business Acquisition, Pro Forma Net Income (Loss) |  |  | 2,277,358,000 |  |
Business Acquisition, Proforma Net Income Available to Common Shares |  |  | $ 2,183,756,000 |  |
Business Acquisition, Pro Forma Earnings Per Share, Basic | $ / shares |  |  | $ 6.07 |  |
Business Acquisition, Proforma Weighted Average Common Shares Basic | shares |  |  | 359,688,000 |  |
Business Acquisition, Pro Forma Earnings Per Share, Diluted | $ / shares |  |  | $ 6.05 |  |
Business Acquisition, Proforma Weighted Average Number Of Shares Diluted | shares |  |  | 375,861,000 |  |
Severance Costs |  |  | $ 54,100,000 |  |
Archstone Transaction [Member] | DelayedDrawTermLoan [Member] |  |  |  |  |
Term Loan Principal Amount |  |  | 750,000,000 |  |
Archstone Transaction [Member] | Positive Outcome of Litigation [Member] |  |  |  |  |
Depreciable property Abstract |  |  |  |  |
Income (Loss) from Equity Method Investments | 18,600,000 |  |  |  |
Archstone Transaction [Member] | ERPOP [Member] |  |  |  |  |
Depreciable property Abstract |  |  |  |  |
Business Acquisition, Pro Forma Revenue |  |  | 2,485,438,000 |  |
Business Acquisition, Proforma Income Loss From Continuing Operations |  |  | 203,286,000 |  |
Business Acquisition, Proforma Income Loss From Discontinued Operations Net Of Tax |  |  | 2,074,072,000 |  |
Business Acquisition, Pro Forma Net Income (Loss) |  |  | 2,277,358,000 |  |
Business Acquisition, Proforma Net Income Available to Units |  |  | $ 2,273,798,000 |  |
Business Acquisition, Pro Forma Earnings Per Share, Basic | $ / shares |  |  | $ 6.07 |  |
Business Acquisition, Proforma Weighted Average Limited Partnership And General Partnership Units Outstanding Basic | shares |  |  | 373,421,000 |  |
Business Acquisition, Pro Forma Earnings Per Share, Diluted | $ / shares |  |  | $ 6.05 |  |
Business Acquisition, Proforma Weighted Average Number Of Limited Partnership And General Partnership Unit Outstanding Diluted | shares |  |  | 375,861,000 |  |
Archstone Transaction [Member] | Consolidated Properties [Member] |  |  |  |  |
Uncompleted Development Properties Acquired |  |  | 2 |  |
Archstone Transaction [Member] | Unconsolidated Properties [Member] |  |  |  |  |
Uncompleted Development Properties Acquired |  |  | 2 |  |
Assets [Member] |  |  |  |  |
Depreciable property Abstract |  |  |  |  |
Below Market Lease, Gross | 178,251,000 | 178,251,000 |  |  | 178,251,000
Finite-Lived Intangible Asset, Off-market Lease, Favorable, Gross | 1,260,000 | 1,260,000 |  |  |
Liability [Member] |  |  |  |  |
Depreciable property Abstract |  |  |  |  |
Below Market Lease, Gross | 5,270,000 | 5,270,000 |  |  | $ 8,040,000
Off-market Lease, Unfavorable | $ 2,400,000 | $ 2,400,000 |  |  |

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- Definition Number of operating properties for which the Company owns the building and improvements and leases the underlying land under long-term ground leases. + References No definition available. + Details
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- Definition Total number of units associated with the property or properties acquired from unaffiliated third parties during the period. + References No definition available. + Details
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- Definition Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life. + References No definition available. + Details
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460 + Details
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- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463 + Details
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- Definition The current amount of expenditures for a real estate project that has not yet been completed. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.10) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Phase -URI http://asc.fasb.org/extlink&oid=49177889 + Details
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- Definition This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired. + References No definition available. + Details
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- Definition This element represents the identifiable intangible asset established upon acquisition based on a favorable difference between the terms of an acquired lease and the current market terms for that lease at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.15) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines. + References No definition available. + Details
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- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.12) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 + Details
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- Definition Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(d)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Amount before accumulated depletion of real estate held for productive use, excluding land held for sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765 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 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount of land available for development. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),1(d)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition This element represents a liability associated with the acquisition of an off-market lease when the terms of the lease are unfavorable to the market terms for the lease at the date of acquisition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.24) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. + 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=56944662&loc=d3e3213-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 + Details
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- Definition Amount of cash inflow from the sale of other assets as part of operating activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585 + Details
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