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Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Basic earnings per share: |  |
Net income | $ 143,637 | $ 89,798
Weighted average common shares outstanding - basic (in shares) | 370,908 | 341,009
Basic earnings per share (in dollars per share) | $ 0.39 | $ 0.26
Diluted earnings per share: |  |
Net income | $ 143,637 | $ 89,798
Diluted income available to common shareholders | $ 148,203 | $ 95,660
Weighted average common shares outstanding - basic (in shares) | 370,908 | 341,009
Effect of dilutive securities: |  |
Weighted average common shares outstanding - diluted (in shares) | 391,562 | 402,175
Diluted earnings per share (in dollars per share) | $ 0.38 | $ 0.24
Effective income tax rate | 21.00% | 35.00%
9% Debentures |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Stated interest rate | 9.00% |
2% Notes |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Stated interest rate |  | 2.00%
Diluted earnings per share: |  |
Dilutive securities | $ 0 | $ 823
Effect of dilutive securities: |  |
Dilutive securities (in shares) | 0 | 29,859
5% Notes |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Stated interest rate |  | 5.00%
Diluted earnings per share: |  |
Dilutive securities | $ 0 | $ 1,282
Effect of dilutive securities: |  |
Dilutive securities (in shares) | 0 | 10,791
9% Debentures |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |
Stated interest rate | 9.00% |
Diluted earnings per share: |  |
Dilutive securities | $ 4,566 | $ 3,757
Effect of dilutive securities: |  |
Dilutive securities (in shares) | 19,028 | 19,028
Unvested RSUs |  |
Effect of dilutive securities: |  |
Unvested RSUs (in shares) | 1,626 | 1,488

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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=96948231&loc=d3e4984-109258 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e1252-109256 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(21)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(23)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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