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CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands | Total | Common stock | Paid-in capital | Treasury stock | Accumulated other comprehensive loss | Retained earnings (deficit)
--- | --- | --- | --- | --- | --- | ---
Balance, beginning of year at Dec. 31, 2014 |  | $ 340,047 | $ 1,663,592 | $ (32,937) | $ (81,341) | $ (852,458)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Net common stock issued under share-based compensation plans |  | 50 | (478) |  |  |
Reissuance of treasury stock, net under share-based compensation plans |  |  | (6,894) | 29,575 |  | (29,495)
Tax benefit from share-based compensation |  |  | 2,116 |  |  |
Equity compensation |  |  | 11,902 |  |  |
Other comprehensive income (loss) | $ 20,461 |  |  |  | 20,461 |
Net income | 1,172,000 |  |  |  |  | 1,172,000
Balance, end of year at Dec. 31, 2015 | 2,236,140 | 340,097 | 1,670,238 | (3,362) | (60,880) | 290,047
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Issuance of common stock |  | 18,313 | 113,146 |  |  |
Net common stock issued under share-based compensation plans |  | 990 | (6,020) |  |  |
Reissuance of treasury stock, net under share-based compensation plans |  |  | (130) | 130 |  |
Tax benefit from share-based compensation |  |  | 67 |  |  |
Equity compensation |  |  | 11,373 |  |  |
Reacquisition of convertible junior subordinated debentures-equity component |  |  | (6,337) |  |  |
Purchases of common stock | (147,100) |  |  | (147,127) |  |
Other comprehensive income (loss) | (14,220) |  |  |  | (14,220) |
Net income | 342,517 |  |  |  |  | 342,517
Balance, end of year at Dec. 31, 2016 | 2,548,842 | 359,400 | 1,782,337 | (150,359) | (75,100) | 632,564
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Cumulative effect of share-based compensation accounting standard update |  |  | 49 |  |  | 153
Issuance of common stock |  | 10,386 | 60,903 |  |  |
Net common stock issued under share-based compensation plans |  | 781 | (7,602) |  |  |
Equity compensation |  |  | 14,895 |  |  |
Reissuance of treasury stock, net |  |  |  | 150,359 |  | (21,740)
Other comprehensive income (loss) | 41,739 |  |  |  | 41,739 |
Net income | 355,761 |  |  |  |  | 355,761
Cumulative effect to reclassify certain tax effects from accumulated other comprehensive loss |  |  |  |  | (10,422) | 10,422
Balance, end of year at Dec. 31, 2017 | $ 3,154,526 | $ 370,567 | $ 1,850,582 | $ 0 | $ (43,783) | $ 977,160

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