Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income	$ 9,883	$ 9,910	$ 15,136	$ 14,918
Other comprehensive income:
Cumulative translation adjustments	928	1,358	1,219	284
Changes in market value of investments:
Changes in unrealized gains	39	37	4	121
Total net change in market value of investments	39	37	4	121
Changes in market value of derivatives:
Changes in market value of derivatives, net of taxes of $76, $178, $1 and $10	124	285	2	13
Reclassification adjustment for net losses included in net income, net of benefits of $71, $30, $103 and $100	113	49	186	163
Total net change in market value of derivatives	237	334	188	176
Other comprehensive income	1,204	1,729	1,411	581
Comprehensive income	$ 11,087	$ 11,639	$ 16,547	$ 15,499

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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