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Investment Income (Expense)

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Investments in Associated Companies [Abstract]

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Amount of investment in marketable security, classified as noncurrent.

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Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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Investments - Long-Term Investments (Details) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Feb. 28, 2019 $ / shares	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 15, 2017 $ / shares
Carried at cost:
Total		$ 219,156		$ 219,156		$ 275,836
Total		$ (3,194)	$ 1,855	$ 26,420	$ (408)
Steel Connect, Inc (STCN)
Investments in Associated Companies:
Ownership percentage		29.00%		29.00%		29.40%
Long-Term Investments Balance		$ 9,819		$ 9,819		$ 26,547
Income (Loss) from Equity Method Investments		$ 968	1,128	$ 14,839	(346)
Aviat Networks, Inc. (Aviat)
Investments in Associated Companies:
Ownership percentage		12.40%		12.40%		12.40%
Long-Term Investments Balance		$ 14,719		$ 14,719		$ 9,417
Income (Loss) from Equity Method Investments		$ (1,877)	25	$ (4,003)	(202)
Other
Investments in Associated Companies:
Ownership percentage		0.00%		0.00%		43.80%
Long-Term Investments Balance		$ 0		$ 0		$ 1,223
Income (Loss) from Equity Method Investments		0	0	(460)	0
Corporate securities
Carried at cost:
Cost		12,753		12,753		58,495
Corporate securities \| Net investment (loss) gain
Equity securities - U.S.
Long-Term Investments Balance		159,212		159,212		186,777
Collateralized debt securities \| Net investment (loss) gain
Equity securities - U.S.
Long-Term Investments Balance		433		433		855
Convertible notes \| Steel Connect, Inc (STCN)
Equity securities - U.S.
Long-Term Investments Balance		9,055		9,055		11,839
Marketable Securities, Realized Gain (Loss)		(530)	246	2,784	1,752
Carried at cost:
Cost		14,943		14,943
Gross unrealized loss		(5,888)		(5,888)
Preferred stock \| Steel Connect, Inc (STCN)
Equity securities - U.S.
Long-Term Investments Balance		25,918		25,918		$ 39,178
Marketable Securities, Realized Gain (Loss)		(1,755)	$ 456	13,260	$ (1,612)
Carried at cost:
Cost		$ 35,633		$ 35,633
Debt conversion price (in dollars per share) \| $ / shares							$ 1.96
Senior Notes \| Convertible Senior Note Due 2024 \| Common Stock \| Steel Connect, Inc (STCN)
Carried at cost:
Debt Instrument, Convertible, Conversion Ratio	0.4213
Senior Notes \| Steel Connect, Inc (STCN) \| Convertible Senior Note Due 2024 \| Common Stock \| Steel Connect, Inc (STCN)
Carried at cost:
Debt conversion price (in dollars per share) \| $ / shares	$ 2.37
Ownership percentage if converted				48.70%