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Earnings Per Share Information about Dilutive and Anti-Dilute Shares (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	780
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	1,873	1,284	1,750	1,338
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	2,812	3,094	2,774	3,071
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