XML 58 R37.htm IDEA: XBRL DOCUMENT
v3.20.4

LEASES: (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2020
LEASES: |
Schedule of the operating lease expense recognized | The operating lease expense recognized in the years ended December 31, 2020 and 2019 was classified as follows (in millions): ​
​ | ​ | ​ | ​ | ​ | ​ | ​
Classification |  | 2020 |  | 2019
Cost of sales (exclusive of depreciation, amortization and depletion) |  | $ | 114.4 | ​ | $ | 114.4
Selling, general and administrative | ​ |  | 0.2 | ​ |  | 0.2
Exploration | ​ |  | 0.2 | ​ |  | 0.2
Total lease expense |  | $ | 114.8 | ​ | $ | 114.8
Schedule of Maturities of lease liabilities | ​
​ | ​ | ​ | ​
​ | ​ | Lease liabilities
Year |  | (in millions)
2021 |  | $ | 114.7
2022 | ​ |  | 113.7
2023 | ​ |  | 112.3
2024 | ​ |  | 104.7
2025 | ​ |  | 103.7
After 2025 | ​ |  | 723.0
Total lease payments |  | $ | 1,272.1
Less: interest on lease liabilities | ​ |  | (293.1)
Present value of lease payments |  | $ | 979.0

X
- Definition Tabular disclosure of lessee's lease cost. Includes, but is not limited to, interest expense for finance lease, amortization of right-of-use asset for finance lease, operating lease cost, short-term lease cost, variable lease cost and sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
Name: | us-gaap_LeaseCostTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_LeasesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of undiscounted cash flows of lessee's operating lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating lease liability recognized in statement of financial position. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration