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Shareholders’ Equity (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 63 Months Ended | 114 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2015 | Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2020 | Dec. 31, 2019 | Dec. 31, 2011 | Dec. 31, 2008
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  | 195,000,000 |  | 195,000,000 | 195,000,000 | 195,000,000 |  |
Common stock, par value (in dollars per share) |  | $ 0.01 |  | $ 0.01 | $ 0.01 | $ 0.01 |  |
Common stock, shares issued (in shares) |  | 96,671,355 |  | 96,671,355 | 96,671,355 | 96,372,182 |  |
Common stock, shares, outstanding (in shares) |  | 89,484,834 |  | 89,484,834 | 89,484,834 | 89,185,661 |  |
Preferred stock, shares authorized (in shares) |  | 5,000,000 |  | 5,000,000 | 5,000,000 | 5,000,000 |  |
Preferred stock par value (in dollars per share) |  | $ 0.01 |  | $ 0.01 | $ 0.01 | $ 0.01 |  |
Preferred shares issued (in shares) |  |  |  |  |  |  |  | 160,000
Number of shares issued for each share of preferred stock (in shares) |  | 100 |  | 100 | 100 |  |  |
Stock repurchase program, authorized amount | $ 130,000,000.0 |  |  |  |  |  | $ 60,000,000.0 |
Stock repurchase program, authorized, increase amount | $ 70,000,000.0 |  |  |  |  |  |  |
Treasury stock, shares, acquired (in shares) |  |  |  | 0 | 7,186,521 |  |  |
Treasury stock, value, acquired, cost method |  |  |  |  | $ 86,300,000 |  |  |
Stock repurchase program, remaining authorized repurchase amount |  | $ 43,700,000 |  | $ 43,700,000 | $ 43,700,000 |  |  |
Series A Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Preferred shares outstanding (in shares) |  | 66,039 |  | 66,039 | 66,039 | 67,323 |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance (in shares) |  | 67,323 | 71,967 |  |  |  |  |
Conversion of convertible preferred stock (in shares) |  | (1,284) | (3,392) |  |  |  |  |
Issuance for stock compensation plans (in shares) |  | 0 | 0 |  |  |  |  |
Ending balance (in shares) |  | 66,039 | 68,575 | 66,039 | 66,039 |  |  |
Treasury [Member] |  |  |  |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance (in shares) |  | 7,186,521 | 7,186,521 |  |  |  |  |
Conversion of convertible preferred stock (in shares) |  | 0 | 0 |  |  |  |  |
Issuance for stock compensation plans (in shares) |  | 0 | 0 |  |  |  |  |
Ending balance (in shares) |  | 7,186,521 | 7,186,521 | 7,186,521 | 7,186,521 |  |  |
Common stock [Member] |  |  |  |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance (in shares) |  | 89,185,661 | 88,103,440 |  |  |  |  |
Conversion of convertible preferred stock (in shares) |  | 128,389 | 339,166 |  |  |  |  |
Issuance for stock compensation plans (in shares) |  | 170,784 | 451,161 |  |  |  |  |
Ending balance (in shares) |  | 89,484,834 | 88,893,767 | 89,484,834 | 89,484,834 |  |  |

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