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Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Debt Instrument [Line Items] |  |  |
Deferred finance costs | [1] | $ 27,174 | $ 17,883
Senior notes | 6.625% Senior notes 2023 |  |  |
Debt Instrument [Line Items] |  |  |
Deferred finance costs |  | 6,000 |
Senior notes | 6.000% Senior notes 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Deferred finance costs |  | 10,900 |
Senior notes | 6.375% Senior Notes 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Deferred finance costs |  | 10,100 |
Carrying value | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Fair value of notes |  | 1,600,000 |
Fair value | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Fair value of notes |  | $ 1,600,000 |
[1] | In accordance with ASU 2015-03, loan issuance cost related to the Notes have been presented as a reduction to the Notes. At December 31, 2016, total unamortized debt issuance costs were $6.0 million for the 2023 Notes, $10.9 million for the 2024 Notes, and $10.1 million for the 2025 Notes. In addition, loan commitment fee costs for the construction loan agreement described immediately below were $0.1 million at December 31, 2016.

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