Variable Interest Entities	12 Months Ended
Dec. 31, 2019
Variable Interest Entities
Variable Interest Entities	19. Variable Interest Entities Following is a description of our financial interests in unconsolidated and consolidated variable interest entities that we consider significant: Low-Income Housing Properties and Refined Coal Facility Investments We do not consolidate our investments in entities established to manage low-income housing properties and a refined coal facility because we are not the primary beneficiary of these entities as we do not have the power to individually direct the activities of these entities. Accordingly, we account for these investments under the equity method of accounting. Our aggregate investment balance in these entities was $309 million and $189 million as of December 31, 2019 and 2018, respectively. The debt balance related to our investments in low-income housing properties was $269 million and $151 million as of December 31, 2019 and 2018, respectively. Additional information related to these investments is discussed in Note 9. Trust Funds for Final Capping, Closure, Post-Closure or Environmental Remediation Obligations Unconsolidated Variable Interest Entities — Trust funds that are established for both the benefit of the Company and the host community in which we operate are not consolidated because we are not the primary beneficiary of these entities as (i) we do not have the power to direct the significant activities of the trusts or (ii) power over the trusts’ significant activities is shared. Our interests in these trusts are accounted for as investments in unconsolidated entities and receivables. These amounts are recorded in other receivables, investments in unconsolidated entities and long-term other assets in our Consolidated Balance Sheets, as appropriate. We also reflect our share of the unrealized gains and losses on available-for-sale securities held by these trusts as a component of our accumulated other comprehensive income (loss). Our investments and receivables related to these trusts had an aggregate carrying value of $101 million and $92 million as of December 31, 2019 and 2018, respectively. Consolidated Variable Interest Entities — Trust funds for which we are the sole beneficiary are consolidated because we are the primary beneficiary. These trust funds are recorded in restricted trust and escrow accounts in our Consolidated Balance Sheets. Unrealized gains and losses on available-for-sale securities held by these trusts are recorded as a component of accumulated other comprehensive income (loss). These trusts had a fair value of $109 million and $103 million as of December 31, 2019 and 2018, respectively.

Variable Interest Entities

12 Months Ended

Dec. 31, 2019

19. Variable Interest Entities

Following is a description of our financial interests in unconsolidated and consolidated variable interest entities that we consider significant:

Low-Income Housing Properties and Refined Coal Facility Investments

We do not consolidate our investments in entities established to manage low-income housing properties and a refined coal facility because we are not the primary beneficiary of these entities as we do not have the power to individually direct the activities of these entities. Accordingly, we account for these investments under the equity method of accounting. Our aggregate investment balance in these entities was $309 million and $189 million as of December 31, 2019 and 2018, respectively. The debt balance related to our investments in low-income housing properties was $269 million and $151 million as of December 31, 2019 and 2018, respectively. Additional information related to these investments is discussed in Note 9.

Trust Funds for Final Capping, Closure, Post-Closure or Environmental Remediation Obligations

Unconsolidated Variable Interest Entities — Trust funds that are established for both the benefit of the Company and the host community in which we operate are not consolidated because we are not the primary beneficiary of these entities as (i) we do not have the power to direct the significant activities of the trusts or (ii) power over the trusts’ significant activities is shared. Our interests in these trusts are accounted for as investments in unconsolidated entities and receivables. These amounts are recorded in other receivables, investments in unconsolidated entities and long-term other assets in our Consolidated Balance Sheets, as appropriate. We also reflect our share of the unrealized gains and losses on available-for-sale securities held by these trusts as a component of our accumulated other comprehensive income (loss). Our investments and receivables related to these trusts had an aggregate carrying value of $101 million and $92 million as of December 31, 2019 and 2018, respectively.

Consolidated Variable Interest Entities — Trust funds for which we are the sole beneficiary are consolidated because we are the primary beneficiary. These trust funds are recorded in restricted trust and escrow accounts in our Consolidated Balance Sheets. Unrealized gains and losses on available-for-sale securities held by these trusts are recorded as a component of accumulated other comprehensive income (loss). These trusts had a fair value of $109 million and $103 million as of December 31, 2019 and 2018, respectively.