INCOME TAXES: - Allocated Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Earnings (loss) from continuing operations	$ (45,409)	$ (65,723)	$ (45,184)
Earnings from discontinued operations	470,346	42,952	49,718
Tax shortfall (excess tax benefits) from share-based compensation	0	0	(2,183)
Total	$ 424,937	$ (22,771)	$ 2,351

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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The sum of the tax effects of all items occurring during the period that have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of income tax expense (benefit) for continuing operations, discontinued operations, other comprehensive income, and items charged (credited) directly to shareholders' equity.

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