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Earnings Per Share Information about Dilutive and Anti-Dilute Shares (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Antidilutive shares due to proceeds from exercising exceeded price of shares [Domain]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	3,280	1,981	3,482	1,553
2.5% Convertible Senior Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	14,205		14,205
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights	3,447	2,772	3,291	2,754