Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 7,669	$ 11,476
Other comprehensive income:
Cumulative translation adjustments	977	(432)
Changes in market value of investments:
Changes in unrealized (losses) gains	(59)	44
Total net change in market value of investments	(59)	44
Changes in market value of derivatives:
Changes in market value of derivatives, net of taxes of $4 and $86	6	138
Reclassification adjustment for net gains (losses) included in net income, net of taxes (benefits) of $460 and ($63)	863	(106)
Total net change in market value of derivatives	869	32
Other comprehensive income (loss)	1,787	(356)
Total comprehensive income	$ 9,456	$ 11,120

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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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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