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Leases - Balance Sheet Location (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Operating leases |  |
Operating lease right of use assets | $ 15,010 | $ 16,069
Other accrued liabilities | 2,528 | 2,553
Long-term operating lease liabilities | 12,482 | 13,516
Total operating lease liabilities | 15,010 | 16,069
Finance leases |  |
Property, plant, and equipment | 1,163 | 1,116
Accumulated amortization | (943) | (869)
Property, plant, and equipment - net | 220 | 247
Current maturities of long-term debt | 124 | 119
Long-term debt | 96 | 128
Total finance lease liabilities | $ 220 | $ 247
Operating lease, liability, current, statement of financial position | Other accrued liabilities | Other accrued liabilities
Finance lease, right-of-use asset, statement of financial position | Property, plant, and equipment - net (Note 8) | Property, plant, and equipment - net (Note 8)
Finance lease, liability, current, statement of financial position | us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent | us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent
Finance lease, liability, noncurrent, statement of financial position | Long-term portion | Long-term portion

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- Definition 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=123408670&loc=SL77918701-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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