Commitments and Contingencies	9 Months Ended
Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments In connection with our development, redevelopment and capital improvement activities, we have entered into various construction related contracts. Additionally, pursuant to financing and/or other arrangements on our One Canal Street, Lincoln Place, and The Preserve at Marin projects, we are contractually obligated to complete the planned activities. As of September 30, 2014, our commitments related to these capital activities totaled approximately $189.6 million, most of which we expect to incur during the next 12 months. We also enter into certain commitments for future purchases of goods and services in connection with the operations of our apartment communities. Those commitments generally have terms of one year or less and reflect expenditure levels comparable to our historical expenditures. Tax Credit Arrangements We are required to manage certain consolidated real estate partnerships in compliance with various laws, regulations and contractual provisions that apply to our historic and low-income housing tax credit syndication arrangements. In some instances, noncompliance with applicable requirements could result in projected tax benefits not being realized and require a refund or reduction of investor capital contributions, which are reported as deferred income in our condensed consolidated balance sheet, until such time as our obligation to deliver tax benefits is relieved. The remaining compliance periods for our tax credit syndication arrangements range from less than one year to 12 years. We do not anticipate that any material refunds or reductions of investor capital contributions will be required in connection with these arrangements. Income Taxes On October 25, 2012, the Internal Revenue Service, or IRS, issued Final Partnership Administrative Adjustments with respect to the Aimco Operating Partnership’s 2006 and 2007 tax years. On January 18, 2013, AIMCO-GP, Inc., in its capacity as tax matters partner of the Aimco Operating Partnership, filed a petition challenging those adjustments in the United States Tax Court in Washington, D.C. On December 20, 2013, the parties agreed on the terms of a settlement of that litigation. On July 23, 2014, the United States Tax Court approved the stipulated decision document previously filed by the IRS and the Aimco Operating Partnership. The settlement had no material effect on our unrecognized tax benefits, financial condition or results of operations. On March 19, 2014, the IRS notified the Aimco Operating Partnership of its intent to audit the 2011 and 2012 tax years. We do not believe the audit will have any material effect on our unrecognized tax benefits, financial condition or results of operations. Legal Matters In addition to the matters described below, we are a party to various legal actions and administrative proceedings arising in the ordinary course of business, some of which are covered by our general liability insurance program, and none of which we expect to have a material adverse effect on our consolidated financial condition, results of operations or cash flows. Limited Partnerships In connection with our acquisitions of interests in real estate partnerships, we are sometimes subject to legal actions, including allegations that such activities may involve breaches of fiduciary duties to the partners of such real estate partnerships or violations of the relevant partnership agreements. We may incur costs in connection with the defense or settlement of such litigation. We believe that we comply with our fiduciary obligations and relevant partnership agreements. Although the outcome of any litigation is uncertain, we do not expect any such legal actions to have a material adverse effect on our consolidated financial condition, results of operations or cash flows. Environmental Various federal, state and local laws subject apartment community owners or operators to liability for management, and the costs of removal or remediation, of certain potentially hazardous materials that may be present at an apartment community, including lead-based paint, asbestos, polychlorinated biphenyls, petroleum-based fuels, and other miscellaneous materials that may have impacted an apartment community as a result of historical property uses or off-site sources. Such laws often impose liability without regard to fault or whether the owner or operator knew of, or was responsible for, the release or presence of such materials. The presence of, or the failure to manage or remediate properly, these materials may adversely affect occupancy at affected apartment communities and the ability to sell or finance affected apartment communities. In addition, governmental agencies may bring claims for costs associated with investigation and remediation actions, damages to natural resources and for potential fines or penalties in connection therewith or with respect to the improper management of hazardous materials. Moreover, the presence of hazardous materials at an apartment community could result in claims by private plaintiffs for personal injury, disease, disability or other infirmities. Various laws also impose cleanup liability on anyone who arranges for the disposal or treatment of these materials at an off-site facility owned by a third party (such as a landfill) even if the treatment or disposal facility is properly licensed and operated in compliance with applicable law. In connection with the ownership, operation and management of apartment communities, we could potentially be responsible for environmental liabilities or costs associated with our current apartment communities, communities we acquire or manage in the future, or communities we previously owned or operated in the past. We are engaged in discussions with the Environmental Protection Agency, or EPA, regarding environmental conditions identified in the vicinity of an Indiana apartment community that has not been owned by us since 2008. The EPA alleges that a dry cleaner that operated on our former property, prior to our ownership, discharged hazardous materials into the sanitary sewers and the environment. Based on our review of the scientific data, we believe that the presence of hazardous materials in the area under review by the EPA is attributable to neighboring property owners (including an auto parts manufacturer), and not the dry cleaner. Although the outcome of these discussions is uncertain, we do not expect the resolution to have a material adverse effect on our consolidated financial condition, results of operations or cash flows. We have determined that our legal obligations to remove or remediate certain potentially hazardous materials may be conditional asset retirement obligations, as defined in GAAP. Except in limited circumstances where the asset retirement activities are expected to be performed in connection with a planned construction project or apartment community casualty, we believe that the fair value of our asset retirement obligations cannot be reasonably estimated due to significant uncertainties in the timing and manner of settlement of those obligations. Asset retirement obligations that are reasonably estimable as of September 30, 2014, are immaterial to our consolidated financial condition, results of operations and cash flows.

Commitments and Contingencies

Commitments

In connection with our development, redevelopment and capital improvement activities, we have entered into various construction related contracts. Additionally, pursuant to financing and/or other arrangements on our One Canal Street, Lincoln Place, and The Preserve at Marin projects, we are contractually obligated to complete the planned activities. As of September 30, 2014, our commitments related to these capital activities totaled approximately $189.6 million, most of which we expect to incur during the next 12 months. We also enter into certain commitments for future purchases of goods and services in connection with the operations of our apartment communities. Those commitments generally have terms of one year or less and reflect expenditure levels comparable to our historical expenditures.

Tax Credit Arrangements

We are required to manage certain consolidated real estate partnerships in compliance with various laws, regulations and contractual provisions that apply to our historic and low-income housing tax credit syndication arrangements. In some instances, noncompliance with applicable requirements could result in projected tax benefits not being realized and require a refund or reduction of investor capital contributions, which are reported as deferred income in our condensed consolidated balance sheet, until such time as our obligation to deliver tax benefits is relieved. The remaining compliance periods for our tax credit syndication arrangements range from less than one year to 12 years. We do not anticipate that any material refunds or reductions of investor capital contributions will be required in connection with these arrangements.

Income Taxes

On October 25, 2012, the Internal Revenue Service, or IRS, issued Final Partnership Administrative Adjustments with respect to the Aimco Operating Partnership’s 2006 and 2007 tax years. On January 18, 2013, AIMCO-GP, Inc., in its capacity as tax matters partner of the Aimco Operating Partnership, filed a petition challenging those adjustments in the United States Tax Court in Washington, D.C. On December 20, 2013, the parties agreed on the terms of a settlement of that litigation. On July 23, 2014, the United States Tax Court approved the stipulated decision document previously filed by the IRS and the Aimco Operating Partnership. The settlement had no material effect on our unrecognized tax benefits, financial condition or results of operations.

On March 19, 2014, the IRS notified the Aimco Operating Partnership of its intent to audit the 2011 and 2012 tax years. We do not believe the audit will have any material effect on our unrecognized tax benefits, financial condition or results of operations.

Legal Matters

In addition to the matters described below, we are a party to various legal actions and administrative proceedings arising in the ordinary course of business, some of which are covered by our general liability insurance program, and none of which we expect to have a material adverse effect on our consolidated financial condition, results of operations or cash flows.

Limited Partnerships

In connection with our acquisitions of interests in real estate partnerships, we are sometimes subject to legal actions, including allegations that such activities may involve breaches of fiduciary duties to the partners of such real estate partnerships or violations of the relevant partnership agreements. We may incur costs in connection with the defense or settlement of such litigation. We believe that we comply with our fiduciary obligations and relevant partnership agreements. Although the outcome of any litigation is uncertain, we do not expect any such legal actions to have a material adverse effect on our consolidated financial condition, results of operations or cash flows.

Environmental

Various federal, state and local laws subject apartment community owners or operators to liability for management, and the costs of removal or remediation, of certain potentially hazardous materials that may be present at an apartment community, including lead-based paint, asbestos, polychlorinated biphenyls, petroleum-based fuels, and other miscellaneous materials that may have impacted an apartment community as a result of historical property uses or off-site sources. Such laws often impose liability without regard to fault or whether the owner or operator knew of, or was responsible for, the release or presence of such materials. The presence of, or the failure to manage or remediate properly, these materials may adversely affect occupancy at affected apartment communities and the ability to sell or finance affected apartment communities. In addition, governmental agencies may bring claims for costs associated with investigation and remediation actions, damages to natural resources and for potential fines or penalties in connection therewith or with respect to the improper management of hazardous materials. Moreover, the presence of hazardous materials at an apartment community could result in claims by private plaintiffs for personal injury, disease, disability or other infirmities. Various laws also impose cleanup liability on anyone who arranges for the disposal or treatment of these materials at an off-site facility owned by a third party (such as a landfill) even if the treatment or disposal facility is properly licensed and operated in compliance with applicable law. In connection with the ownership, operation and management of apartment communities, we could potentially be responsible for environmental liabilities or costs associated with our current apartment communities, communities we acquire or manage in the future, or communities we previously owned or operated in the past.

We are engaged in discussions with the Environmental Protection Agency, or EPA, regarding environmental conditions identified in the vicinity of an Indiana apartment community that has not been owned by us since 2008. The EPA alleges that a dry cleaner that operated on our former property, prior to our ownership, discharged hazardous materials into the sanitary sewers and the environment. Based on our review of the scientific data, we believe that the presence of hazardous materials in the area under review by the EPA is attributable to neighboring property owners (including an auto parts manufacturer), and not the dry cleaner. Although the outcome of these discussions is uncertain, we do not expect the resolution to have a material adverse effect on our consolidated financial condition, results of operations or cash flows.

We have determined that our legal obligations to remove or remediate certain potentially hazardous materials may be conditional asset retirement obligations, as defined in GAAP. Except in limited circumstances where the asset retirement activities are expected to be performed in connection with a planned construction project or apartment community casualty, we believe that the fair value of our asset retirement obligations cannot be reasonably estimated due to significant uncertainties in the timing and manner of settlement of those obligations. Asset retirement obligations that are reasonably estimable as of September 30, 2014, are immaterial to our consolidated financial condition, results of operations and cash flows.