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Long-Term Debt (Details) - USD ($) |  |  |  |  |  |  |  | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 12, 2016 | Jun. 22, 2015 | May 21, 2015 | Nov. 17, 2014 | May 20, 2013 | Jun. 29, 2012 | Nov. 08, 2011 | Mar. 31, 2016 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Aug. 12, 2016 | Jun. 05, 2015 | May 20, 2015
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 2,766,719,000 | $ 2,315,970,000 |  |  |  |
Gains (Losses) on Extinguishment of Debt |  |  |  |  |  |  |  |  | 15,722,000 | (16,578,000) | $ 0 |  |  |
Gains (Losses) on Extinguishment of Debt, Non-Cash Portion |  |  |  |  |  |  |  |  | 15,722,000 | (4,123,000) | 0 |  |  |
Net proceeds from debt issuance |  |  |  |  |  |  |  |  | 491,640,000 | 490,951,000 | 589,991,000 |  |  |
Proceeds from Convertible Debt Net of Issuance Costs |  |  |  |  |  |  |  |  | 166,617,000 | 0 | 0 |  |  |
Convertible Debt, Noncurrent |  |  |  |  |  |  |  |  | 130,856,000 | 0 |  |  |  |
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Net of Issuance Costs and Deferred Taxes |  |  |  |  |  |  |  |  | 33,575,000 |  |  |  |  |
Capped Call Transaction Costs |  |  |  |  |  |  |  |  | $ 24,195,000 |  |  |  |  |
Capped Call, Cap Price |  |  |  |  |  |  |  |  | $ 60.00 |  |  |  |  |
Interest Costs, Capitalized During Period |  |  |  |  |  |  |  |  | $ 17,000,000 | 25,100,000 | $ 16,200,000 |  |  |
Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  | 2,803,736,000 | 2,350,000,000 |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 37,017,000 | 34,030,000 |  |  |  |
Debt Instrument, Covenant Compliance, Dividends Excluded From Computation |  |  |  |  |  |  |  |  | 6,500,000 |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  |  |  |  |  |  |  | $ 46,300,000 |  |  |  |  |  |
Debt Instrument, Repurchased Settlement Amount |  |  |  |  |  |  |  | 29,900,000 |  |  |  |  |  |
Gains (Losses) on Extinguishment of Debt |  |  |  |  |  |  |  | 15,722,000 |  |  |  |  |  |
Debt Instrument, Repurchase Discount |  |  |  |  |  |  |  | 16,400,000 |  |  |  |  |  |
Gains (Losses) on Extinguishment of Debt, Non-Cash Portion |  |  |  |  |  |  |  | (700,000) |  |  |  |  |  |
6.50% Senior Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 3,372,000 | 4,106,000 |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 343,583,000 | 345,894,000 |  |  |  |
6.50% Senior Notes Due 2021 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  | 6.50% |  | 6.50% |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  | $ 350,000,000 |  | $ 346,955,000 | 350,000,000 |  |  |  |
Debt Instrument, Repurchased Face Amount |  |  |  |  |  |  |  | 3,100,000 |  |  |  |  |  |
Debt Instrument, Repurchased Settlement Amount |  |  |  |  |  |  |  | 2,300,000 |  |  |  |  |  |
Net proceeds from debt issuance |  |  |  |  |  |  | 343,100,000 |  |  |  |  |  |  |
Debt Issuance Costs, Gross |  |  |  |  |  |  | $ 6,900,000 |  |  |  |  |  |  |
6.125% Senior Notes Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 6,979,000 | 8,714,000 |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 554,817,000 | 591,286,000 |  |  |  |
6.125% Senior Notes Due 2022 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 6.125% |  |  |  |  | 6.125% |  |  |  |  |
Debt Instrument, Face Amount |  |  |  | $ 600,000,000 |  |  |  |  | $ 561,796,000 | 600,000,000 |  |  |  |
Debt Instrument, Repurchased Face Amount |  |  |  |  |  |  |  | 38,200,000 |  |  |  |  |  |
Debt Instrument, Repurchased Settlement Amount |  |  |  |  |  |  |  | 24,300,000 |  |  |  |  |  |
Net proceeds from debt issuance |  |  |  | 590,000,000 |  |  |  |  |  |  |  |  |  |
Debt Issuance Costs, Gross |  |  |  | $ 10,000,000 |  |  |  |  |  |  |  |  |  |
6.50% Senior Notes Due 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 4,436,000 | 5,231,000 |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 390,549,000 | 394,769,000 |  |  |  |
6.50% Senior Notes Due 2023 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  | 6.50% |  |  | 6.50% |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  | $ 400,000,000 |  |  | $ 394,985,000 | 400,000,000 |  |  |  |
Debt Instrument, Repurchased Face Amount |  |  |  |  |  |  |  | 5,000,000 |  |  |  |  |  |
Debt Instrument, Repurchased Settlement Amount |  |  |  |  |  |  |  | $ 3,300,000 |  |  |  |  |  |
Net proceeds from debt issuance |  |  |  |  |  | 392,100,000 |  |  |  |  |  |  |  |
Debt Issuance Costs, Gross |  |  |  |  |  | $ 7,900,000 |  |  |  |  |  |  |  |
5% Senior Notes Due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 6,533,000 | 7,455,000 |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 493,467,000 | 492,545,000 |  |  |  |
5% Senior Notes Due 2024 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  | 5.00% |  |  |  | 5.00% |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  | $ 500,000,000 |  |  |  | $ 500,000,000 | 500,000,000 |  |  |  |
Net proceeds from debt issuance |  |  |  |  | 490,200,000 |  |  |  |  |  |  |  |  |
Debt Issuance Costs, Gross |  |  |  |  | $ 9,800,000 |  |  |  |  |  |  |  |  |
5.625% Senior Notes Due 2025 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 7,619,000 | 8,524,000 |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 492,381,000 | 491,476,000 |  |  |  |
5.625% Senior Notes Due 2025 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 5.625% |  |  |  |  |  | 5.625% |  |  |  |  |
Debt Instrument, Face Amount |  |  | $ 500,000,000 |  |  |  |  |  | $ 500,000,000 | 500,000,000 |  |  |  |
Net proceeds from debt issuance |  |  | 491,000,000 |  |  |  |  |  |  |  |  |  |  |
Debt Issuance Costs, Gross |  |  | $ 9,000,000 |  |  |  |  |  |  |  |  |  |  |
6.75% Senior Notes Due 2026 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 8,078,000 | 0 |  |  |  |
Senior Notes, net of unamortized deferred financing costs |  |  |  |  |  |  |  |  | $ 491,922,000 | 0 |  |  |  |
6.75% Senior Notes Due 2026 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.75% |  |  |  |  |  |  |  | 6.75% |  |  |  |  |
Debt Instrument, Face Amount | $ 500,000,000 |  |  |  |  |  |  |  | $ 500,000,000 | 0 |  |  |  |
Net proceeds from debt issuance | 491,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Issuance Costs, Gross | $ 8,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |
6.625% Senior Notes Due 2019 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.625%
Debt Instrument, Repurchased Face Amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,500,000 | $ 242,900,000
Gains (Losses) on Extinguishment of Debt |  |  |  |  |  |  |  |  |  | (16,600,000) |  |  |  |
Gains (Losses) on Extinguishment of Debt, Non-Cash Portion |  |  |  |  |  |  |  |  |  | (4,100,000) |  |  |  |
Price per Note Tendered |  |  |  |  |  |  |  |  |  |  |  |  | 1,006.88 | 1,036.88
Debt Instrument, Face Amount, Individual Note |  |  |  |  |  |  |  |  |  |  |  |  | 1,000 | $ 1,000
Percentage of Notes Tendered |  |  |  |  |  |  |  |  |  |  |  |  |  | 69.00%
Debt Instrument, Repurchase Amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,600,000 | $ 256,200,000
Debt Instrument, Repurchase Premium |  |  |  |  |  |  |  |  |  | 12,500,000 |  |  |  |
6.625% Senior Notes Due 2019 [Member] | From February 15, 2015 to February 14, 2016 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchase Amount |  | $ 111,500,000 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Redemption Price, Percentage |  | 103.313% |  |  |  |  |  |  |  |  |  |  |  |
1.50% Senior Convertible Notes Due 2021 [Domain] | Convertible Debt [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  |  | 1.50% |  |  | 1.50% |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  | $ 172,500,000 | $ 0 |  | $ 172,500,000 |  |
Unamortized Debt Issuance Expense |  |  |  |  |  |  |  |  | 4,131,000 |  |  |  |  |
Debt Issuance Costs, Gross |  |  |  |  |  |  |  |  | 5,900,000 |  |  |  |  |
Proceeds from Convertible Debt Net of Issuance Costs |  |  |  |  |  |  |  |  | $ 166,617,000 |  |  |  |  |
Debt Instrument, Convertible, Threshold Trading Days |  |  |  |  |  |  |  |  | 20 |  |  |  |  |
Debt Instrument, Convertible, Threshold Consecutive Trading Days |  |  |  |  |  |  |  |  | 30 days |  |  |  |  |
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger |  |  |  |  |  |  |  |  | 130.00% |  |  |  |  |
Debt Instrument, Convertible, Threshold Business Days, Trading Price Trigger |  |  |  |  |  |  |  |  | 5 days |  |  |  |  |
Debt Instrument, Convertible, Threshold Trading Days, Trading Price Trigger |  |  |  |  |  |  |  |  | 5 days |  |  |  |  |
Debt Instrument, Principal Amount of Note |  |  |  |  |  |  |  |  | $ 1,000 |  |  |  |  |
Debt Instrument, Convertible, Threshold Percentage of Trading Price Trigger |  |  |  |  |  |  |  |  | 98.00% |  |  |  |  |
Debt Instrument, Convertible, Conversion Ratio |  |  |  |  |  |  |  |  | 24.6914 |  |  |  |  |
Debt Instrument, Convertible, Conversion Price |  |  |  |  |  |  |  |  | $ 40.50 |  |  |  |  |
Debt Instrument, Convertible, Comparable Yield |  |  |  |  |  |  |  |  | 7.25% |  |  |  |  |
Debt Instrument, Convertible, Initial Fair Value of Liability Component |  |  |  |  |  |  |  |  |  |  |  | 132,300,000 |  |
Debt Instrument, Convertible, Initial Fair Value of Liability Component |  |  |  |  |  |  |  |  | $ 40,217,000 |  |  | $ 40,217,000 |  |
Interest Expense, Debt |  |  |  |  |  |  |  |  | 3,700,000 |  |  |  |  |
Debt Instrument, Unamortized Discount |  |  |  |  |  |  |  |  | (37,513,000) |  |  |  |  |
Convertible Debt, Noncurrent |  |  |  |  |  |  |  |  | 130,856,000 |  |  |  |  |
Debt Issuance Costs, Gross, Equity Component of Convertible Debt |  |  |  |  |  |  |  |  | (1,375,000) |  |  |  |  |
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt |  |  |  |  |  |  |  |  | (5,267,000) |  |  |  |  |
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Net of Issuance Costs and Deferred Taxes |  |  |  |  |  |  |  |  | $ 33,575,000 |  |  |  |  |

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- Definition Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt, Net of Issuance Costs and Deferred Taxes + References No definition available. + Details
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- Definition The cap rate on a capped call transaction. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract. + References No definition available. + Details
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- Definition Debt Instrument, Convertible, Comparable Yield + References No definition available. + Details
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- Definition The initial amount of the equity component of convertible debt which may be settled in cash upon conversion. + References No definition available. + Details
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- Definition Threshold number of specified business days subsequent to measurement period in which trading price of convertible debt instruments to common stock price must exceed threshold percentage to trigger conversion feature. + References No definition available. + Details
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- Definition Minimum percentage of trading price of convertible debt instruments to common stock price to determine eligibility of conversion + References No definition available. + Details
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- Definition Threshold number of specified trading days that trading price of convertible debt instruments to common stock price must exceed threshold percentage to trigger conversion feature. + References No definition available. + Details
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- Definition Discount realized on debt instrument that was repurchased. + References No definition available. + Details
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- Definition Debt Instrument, Repurchase Premium + References No definition available. + Details
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- Definition Debt Instrument, Repurchased Settlement Amount + References No definition available. + Details
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- Definition Debt Issuance Costs, Gross, Equity Component of Convertible Debt + References No definition available. + Details
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- Definition Gains (Losses) on Extinguishment of Debt, Non Cash Portion + References No definition available. + Details
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- Definition Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 25 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=51819886&loc=SL6014347-161799 + Details
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- Definition Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
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