Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 11,476	$ 5,253
Other comprehensive income:
Cumulative translation adjustments	(432)	291
Changes in market value of investments:
Changes in unrealized gains (losses)	44	(35)
Total net change in market value of investments	44	(35)
Changes in market value of derivatives:
Changes in market value of derivatives, net of taxes (benefit) of $86 and ($82)	138	(116)
Reclassification adjustment for net (losses) gains included in net income, net of (benefits) taxes of ($63) and $39	(106)	67
Total net change in market value of derivatives	32	(49)
Other comprehensive (loss) income	(356)	207
Comprehensive income	$ 11,120	$ 5,460

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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