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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2013
Accounting Policies [Abstract] |
Dilutive and Anti-Dilutive Shares for Earnings per Share [Table Text Block] | The following table details the weighted-average dilutive and anti-dilutive securities related to stock options, RSUs, PSUs, and the 3.50% Senior Convertible Notes for the years presented:
| For the Years Ended December 31,
| 2013 |  | 2012 |  | 2011
| (in thousands)
Dilutive | 1,383 |  |  | — |  |  | 3,809 |
Anti-dilutive | — |  |  | 2,102 |  |  | — |
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] | The following table sets forth the calculations of basic and diluted earnings per share:
| For the Years Ended December 31,
| 2013 |  | 2012 |  | 2011
| (in thousands, except per share amounts)
Net income (loss) | $ | 170,935 |  |  | $ | (54,249 | ) |  | $ | 215,416 |
Basic weighted-average common shares outstanding | 66,615 |  |  | 65,138 |  |  | 63,755 |
Add: dilutive effect of stock options, unvested RSUs, and contingent PSUs | 1,383 |  |  | — |  |  | 2,592 |
Add: dilutive effect of 3.50% Senior Convertible Notes | — |  |  | — |  |  | 1,217 |
Diluted weighted-average common shares outstanding | 67,998 |  |  | 65,138 |  |  | 67,564 |
Basic net income (loss) per common share | $ | 2.57 |  |  | $ | (0.83 | ) |  | $ | 3.38 |
Diluted net income (loss) per common share | $ | 2.51 |  |  | $ | (0.83 | ) |  | $ | 3.19 |
Schedule of Comprehensive Income (Loss) [Table Text Block] | The changes in the balances of components comprising other comprehensive income (loss) are presented in the following table:
| Derivative Reclassification to Earnings |  | Pension Liability Adjustments
| (in thousands)
For the year ended December 31, 2011 |  |  |
Before tax income (loss) | $ | 20,707 |  |  | $ | (2,779 | )
Tax benefit (expense) | (7,710 | ) |  | 984 |
Income (loss), net of tax | $ | 12,997 |  |  | $ | (1,795 | )
For the year ended December 31, 2012 |  |  |
Before tax loss | $ | (3,865 | ) |  | $ | (3,909 | )
Tax benefit | 1,601 |  |  | 1,439 |
Loss, net of tax | $ | (2,264 | ) |  | $ | (2,470 | )
For the year ended December 31, 2013 |  |  |
Before tax income | $ | 1,777 |  |  | $ | 4,005 |
Tax expense | (662 | ) |  | (1,522 | )
Income, net of tax | $ | 1,115 |  |  | $ | 2,483 |

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- Definition Weighted-average dilutive and anti-dilutive securities + References No definition available. + Details
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- Definition Tabular disclosure of components of comprehensive income (loss) including, but not limited to: (a) foreign currency translation adjustments; (b) gains (losses) on foreign currency transactions that are designated as, and are effective as, economic hedges of a net investment in a foreign entity; (c) gains (losses) on intercompany foreign currency transactions that are of a long-term-investment nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements; (d) change in the market value of a futures contract that qualifies as a hedge of an asset reported at fair value; (e) unrealized holding gains (losses) on available-for-sale securities and that resulting from transfers of debt securities from the held-to-maturity category to the available-for-sale category; (f) a net loss recognized as an additional pension liability not yet recognized as net periodic pension cost; and (g) the net gain (loss) and net prior service cost or credit for pension plans and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e526-108580 + Details
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