Net (Loss) Income Per Common Share From Continuing Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net (loss) income from continuing operations	$ (251,086)	$ 107,335	$ 108,657	$ 33,684
Weighted average common shares outstanding	234,106,000	216,210,000	232,278,000	215,360,000
Dilutive effect of stock options and RSUs	0	4,330,000	4,460,000	4,317,000
Anti-dilutive effect of securities	4,400,046
Weighted average common and potential common shares outstanding	234,106,000	235,424,000	248,024,000	233,351,000
Income from continuing operations, per basic share (in USD per share)	$ (1.07)	$ 0.50	$ 0.47	$ 0.16
Income from continuing operations, per diluted share (in USD per share)	$ (1.07)	$ 0.46	$ 0.44	$ 0.14
2007 Junior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of conversion of debt securities, treasury stock method	0	14,883,643	1,734,984	13,673,578
Anti-dilutive effect of securities	398,430
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 23.49	$ 23.93	$ 23.59	$ 24.08
2015 Senior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of conversion of debt securities, treasury stock method	0	0	9,551,342	0
Anti-dilutive effect of securities	11,920,246
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 63.80	$ 65.00	$ 64.07	$ 65.40
2017 Senior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of conversion of debt securities, treasury stock method	0	0	0	0
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 99.50	$ 0.00	$ 99.92	$ 0.00
2017 Junior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of conversion of debt securities, treasury stock method	0	0	0	0
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 97.75	$ 0.00	$ 98.16	$ 0.00

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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