COMMITMENTS AND CONTINGENCIES - Environmental Matters by Site (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||||||
---|---|---|---|---|---|---|---|---|
Jun. 05, 2007 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2012 |
|
Loss contingencies | ||||||||
Reclamation and remediation | $ 10.0 | $ 5.0 | $ 55.0 | $ 21.0 | ||||
Environmental remediation obligations | 466.0 | $ 285.0 | 466.0 | $ 285.0 | $ 279.0 | $ 304.0 | ||
Midnite Mine And Dawn Mill Sites [Member] | ||||||||
Loss contingencies | ||||||||
Environmental remediation obligations | $ 164.0 | $ 164.0 | ||||||
Midnite Mine | ||||||||
Loss contingencies | ||||||||
Department of Interior contribution for past and future cleanup costs | $ 42.0 | |||||||
Environmental remediation | Ross-Adams Mine Site | ||||||||
Loss contingencies | ||||||||
Damages sought | $ 0.3 | |||||||
Newmont USA | ||||||||
Loss contingencies | ||||||||
Percent ownership held by Newmont | 100.00% | 100.00% | ||||||
Dawn Mining Company | ||||||||
Loss contingencies | ||||||||
Percent ownership held by Newmont | 51.00% | 51.00% |