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Fair Value of Financial Instruments (Narrative) (Details) - USD ($) $ in Thousands | Jun. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Debt Instrument [Line Items] |  |  |
Deferred finance costs, net | [1] | $ 30,804 | $ 27,174
Senior notes | 6.625% Senior Notes due 2023 |  |  |
Debt Instrument [Line Items] |  |  |
Deferred finance costs, net |  | 5,600 |
Senior notes | 6.000% Senior Notes due 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Deferred finance costs, net |  | 10,500 |
Senior notes | 6.375% Senior Notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Deferred finance costs, net |  | 14,600 |
Carry 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 costs related to the 2023 Notes, the 2024 Notes and the 2025 Notes (collectively the “Notes”) have been presented as a reduction to the Notes. At June 30, 2017, total unamortized debt issuance costs were $5.6 million for the 2023 Notes, $10.5 million for the 2024 Notes and $14.6 million for the 2025 Notes.

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