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v3.20.1

Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands | Total | Common Stock [Member] | Additional Paid-in Capital [Member] | Retained Earnings [Member]
--- | --- | --- | --- | ---
Balance at Dec. 31, 2018 |  | $ 3,087,884 | $ 878 | $ 992,647 | $ 2,094,359
Balance, Shares at Dec. 31, 2018 |  |  | 87,820 |  |
Net loss |  | (242,872) |  |  | (242,872)
Unrealized holding loss on investments, net of tax | [1] | (194) |  |  | (194)
Common stock issued under employee stock option, employee stock purchase plan and stock purchase plan |  | 3,542 | $ 1 | 3,541 |
Common stock issued under employee stock option, employee stock purchase plan and stock purchase plan, shares |  |  | 140 |  |
Issuance of restricted stock |  |  | $ 10 | (10) |
Issuance of restricted stock, shares |  |  | 978 |  |
Stock-based compensation expense |  | 11,100 |  | 11,100 |
Stock swaps |  | (666) |  | (666) |
Stock swaps, shares |  |  | (20) |  |
Forfeitures of restricted stock, shares |  |  | (6) |  |
Repurchased common stock |  | (78,982) | $ (25) | (28,740) | (50,217)
Repurchased common stock, shares |  |  | (2,525) |  |
Balance at Mar. 31, 2019 |  | 2,779,812 | $ 864 | 977,872 | 1,801,076
Balance, Shares at Mar. 31, 2019 |  |  | 86,387 |  |
Balance at Dec. 31, 2019 |  | 1,498,996 | $ 842 | 987,942 | 510,212
Balance, Shares at Dec. 31, 2019 |  |  | 84,248 |  |
Net loss |  | (18,712) |  |  | (18,712)
Unrealized holding loss on investments, net of tax | [1] | (213) |  |  | (213)
Common stock issued under employee stock option, employee stock purchase plan and stock purchase plan |  | 1,832 | $ 1 | 1,831 |
Common stock issued under employee stock option, employee stock purchase plan and stock purchase plan, shares |  |  | 78 |  |
Issuance of restricted stock |  |  | $ 10 | (10) |
Issuance of restricted stock, shares |  |  | 968 |  |
Stock-based compensation expense |  | 8,035 |  | 8,035 |
Forfeitures of restricted stock, shares |  |  | (19) |  |
Repurchased common stock |  | (2,542) | $ (1) | (2,541) | 0
Repurchased common stock, shares |  |  | (125) |  |
Balance at Mar. 31, 2020 |  | $ 1,487,396 | $ 852 | $ 995,257 | $ 491,287
Balance, Shares at Mar. 31, 2020 |  |  | 85,150 |  |
[1] | Presented within retained earnings on the consolidated balance sheet as the balance is immaterial.

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