Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (62,504)	$ (24,222)
Other comprehensive income (loss):
Cumulative translation adjustments	(2,708)	1,135
Changes in market value of investments:
Changes in unrealized gains (losses), net of tax (benefit) of $29 and ($2), respectively	28	(4)
Total net change in market value of investments	28	(4)
Changes in market value of derivatives:
Changes in market value of derivatives, net of (benefit) tax of ($126), and $189, respectively	(393)	305
Reclassification adjustment for net gains included in net income, net of taxes of $23 and $5, respectively	71	7
Total net change in market value of derivatives	(322)	312
Other comprehensive income (loss)	(3,002)	1,443
Total comprehensive loss	$ (65,506)	$ (22,779)

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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