Leases (Schedule of future maturities of lease liabilities) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Finance
2020	$ 19,120
2021	7,196
2022	783
2023	803
2024	575
Thereafter	0
Total minimum lease payments	28,477
Less amount representing interest	1,222
Present value of minimum lease payments	27,255
Operating
2020	24,065
2021	23,132
2022	13,341
2023	6,504
2024	6,115
Thereafter	15,958
Total minimum lease payments	89,115
Less amount representing interest	14,223
Present value of minimum lease payments	74,892
Mining equipment
Finance
2020	3,699
2021	2,157
2022	0
2023	0
2024	0
Thereafter	0
Total minimum lease payments	5,856
Operating
2020	627
2021	0
2022	0
2023	0
2024	0
Thereafter	0
Total minimum lease payments	$ 627

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Operating Lease [Abstract]

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No definition available.

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Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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-Publisher FASB
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-Topic 842
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-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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-Paragraph 1
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