Net Income (Loss) Per Common Share From Continuing Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) from continuing operations	$ 170,587	$ (109,225)
Weighted average common shares outstanding	229,429,000	214,345,000
Dilutive effect of stock options and RSUs	4,514,000	0
Weighted average common and potential common shares outstanding	242,902,000	214,345,000
Income from continuing operations, per basic share (in USD per share)	$ 0.74	$ (0.51)
Income from continuing operations, per diluted share (in USD per share)	$ 0.70	$ (0.51)
Antidilutive securities excluded from computation of earnings per share, amount		4,159,273
2007 Junior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of 2007 Junior debt	4,128,673	0
Antidilutive securities excluded from computation of earnings per share, amount		12,165,812
Interest rate of subordinated convertible debentures	2.125%
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 23.69	$ 24.23
2015 Senior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of 2007 Junior debt	4,829,550
Interest rate of subordinated convertible debentures	1.625%
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 64.35	65.82
2017 Senior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate of subordinated convertible debentures	1.625%
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 100.35	0.00
2017 Junior Subordinated Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate of subordinated convertible debentures	2.25%
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 98.59	$ 0.00

The weighted average price per share of the conversion feature embedded in the debt instrument.

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