Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (3,603)	$ 89,685	$ (92,535)	$ 62,995
Other comprehensive income (loss):
Cumulative translation adjustments	(1,170)	(195)	(3,319)	3,435
Changes in market value of investments:
Changes in unrealized gains (losses), net of (benefit) taxes of $12, ($22), $21 and ($16), respectively	12	(41)	35	(32)
Total net change in market value of investments	12	(41)	35	(32)
Changes in market value of derivatives:
Changes in market value of derivatives, net of (benefit) taxes of ($53), ($47), ($193) and $299, respectively	(162)	(66)	(601)	497
Reclassification adjustment for net gains (losses) included in net income (loss), net of taxes (benefit) of $51, ($96), $122 and ($238), respectively	157	(157)	382	(382)
Total net change in market value of derivatives	(5)	(223)	(219)	115
Other comprehensive income (loss)	(1,163)	(459)	(3,503)	3,518
Total comprehensive income (loss)	$ (4,766)	$ 89,226	$ (96,038)	$ 66,513

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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