. fin no . 47 2013 in march 2005 , the fasb issued fasb interpretation ( 2018 2018fin 2019 2019 ) no . 47 , 2018 2018accounting for conditional asset retirement obligations 2013 an interpretation of fasb statement no . 143 . 2019 2019 this interpretation clarifies that an entity is required to recognize a liability for a legal obligation to perform asset retirement activities when the retirement is conditional on a future event if the liability 2019s fair value can be reasonably estimated