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Net Cash Provided by (Used in) Operating Activities Equity Component [Domain] Equity Component [Domain] Total property, plant and equipment, net Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization Short-term term loans, variable rate Short term term loan, variable rate [Member] Short term term loan, variable rate [Member] Document Transition Report Document Transition Report Short-term investments (amortized cost of $355,939 in 2020) Short-term Investments Payments of finance lease obligations Finance Lease, Principal Payments Line of Credit Line of Credit [Member] After 1 year through 5 years, Amortized Cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost Recognized actuarial gain Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Factoring of Accounts Receivable [Line Items] Factoring of Accounts Receivable [Line Items] [Line Items] for Factoring of Accounts Receivable [Table] Summary of defined contribution expense Defined Contribution Plan Disclosures [Table Text Block] Dividends Payable, Date Declared Dividends Payable, Date Declared Income Statement [Abstract] Income Statement [Abstract] Restructuring Plan [Domain] Restructuring Plan [Domain] Factoring of Accounts Receivable Factoring of Accounts Receivable [Text Block] Factoring of Accounts Receivable AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Term loan, applicable bank rate plus 1.98%, due December 2028 Term Loan Due December 2028 [Member] Term Loan Due December 2028 [Member]