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Investments in Associated Companies [Abstract]

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Marketable Securities, Noncurrent, Percentage

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Amount, before tax, of unrealized gain 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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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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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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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
	Feb. 28, 2019 $ / shares	Dec. 15, 2017 $ / shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Investments in Associated Companies:
(Income) Loss Recorded in the Consolidated Statements of Operations
Carried at cost:
Total			$ 220,832		$ 275,836
Steel Connect, Inc (STCN)
Investments in Associated Companies:
Ownership percentage			29.20%		29.40%
Long-Term Investments Balance			$ 13,637		$ 26,547
(Income) Loss Recorded in the Consolidated Statements of Operations			$ 11,452	(4,539)
Aviat Networks, Inc. (Aviat)
Investments in Associated Companies:
Ownership percentage			12.40%		12.40%
Long-Term Investments Balance			$ 5,697		$ 9,417
(Income) Loss Recorded in the Consolidated Statements of Operations			$ 3,720	(1,068)
Other
Investments in Associated Companies:
Ownership percentage			43.80%		43.80%
Long-Term Investments Balance			$ 1,683		$ 1,223
(Income) Loss Recorded in the Consolidated Statements of Operations			(460)	0
Corporate securities
Carried at cost:
Cost			41,076		58,495
Corporate securities \| API Group plc (API)
Carried at cost:
Gross Unrealized Gains			126,730		128,282
Corporate securities \| Net investment (loss) gain
Equity securities - U.S.
Long-Term Investments Balance			167,806		186,777
(Income) Loss Recorded in the Consolidated Statements of Operations			1,553	(1,889)
Corporate securities \| Net investment (loss) gain \| Aerojet Rocketdyne Holdings [Member]
Equity securities - U.S.
Long-Term Investments Balance			$ 165,230		$ 180,357
Carried at cost:
Marketable Securities, Noncurrent, Percentage			5.00%		5.00%
Corporate securities \| Net investment (loss) gain \| Babcock And Wilcox Enterprises [Member]
Equity securities - U.S.
Long-Term Investments Balance			$ 1,007		$ 4,989
Carried at cost:
Marketable Securities, Noncurrent, Percentage			2.00%		3.00%
Collateralized debt securities \| Net investment (loss) gain
Equity securities - U.S.
Long-Term Investments Balance			$ 787		$ 855
(Income) Loss Recorded in the Consolidated Statements of Operations			0	0
Convertible notes \| Steel Connect, Inc (STCN)
Equity securities - U.S.
Long-Term Investments Balance			8,189		11,839
(Income) Loss Recorded in the Consolidated Statements of Operations			3,650	343
Corporate obligations \| Corporate obligations
Carried at cost:
Cost			14,943		14,943
Gross Unrealized Gains					3,104
Gross unrealized loss			6,754
Preferred stock \| Steel Connect, Inc (STCN)
Equity securities - U.S.
Long-Term Investments Balance			23,033		$ 39,178
(Income) Loss Recorded in the Consolidated Statements of Operations			16,145	$ (4,117)
Carried at cost:
Cost			$ 35,634
Debt conversion price (in dollars per share) \| $ / shares		$ 1.96
Ownership percentage if converted		48.90%
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