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Long-Term Debt - Additional Information (Details) |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 28, 2016 USD ($) | Sep. 30, 2016 USD ($) day $ / shares | Sep. 30, 2016 USD ($) $ / shares | Sep. 30, 2015 USD ($) | Sep. 30, 2016 USD ($) $ / shares | Sep. 30, 2015 USD ($) | Sep. 15, 2016 USD ($) | Feb. 23, 2016 USD ($) | Feb. 22, 2016 USD ($) | Dec. 31, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Repurchase of senior unsecured debt |  |  |  |  | $ 435,907,000 | $ 0 |  |  |  |
Gain (loss) on extinguishment of debt |  |  | $ (13,793,000) | $ 0 | $ 4,865,000 | 0 |  |  |  |
Ownership percentage, guarantors (as percent) |  |  |  |  | 100.00% |  |  |  |  |
Deferred financing costs |  | $ 35,000,000 | 35,000,000 |  | $ 35,000,000 |  |  |  |  |
Interest Expense [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Amortization of deferred financing costs |  |  | 2,100,000 | 1,600,000 | 6,200,000 | 5,000,000 |  |  |  |
Line of Credit [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit facility amount |  | 2,500,000,000 | 2,500,000,000 |  | 2,500,000,000 |  |  |  |  |
Line of credit facility, current borrowing capacity |  |  |  |  |  |  |  | $ 1,150,000,000.0 | $ 1,525,000,000.0 |
Line of credit facility, amount outstanding |  | 195,000,000 | 195,000,000 |  | 195,000,000 |  |  |  |  |
Outstanding letters of credit |  | 12,300,000 | 12,300,000 |  | 12,300,000 |  |  |  |  |
Line of credit facility, remaining borrowing capacity |  | $ 942,700,000 | $ 942,700,000 |  | $ 942,700,000 |  |  |  |  |
Weighted average interest rate (as percent) |  | 2.00% | 2.00% |  | 2.00% |  |  |  |  | 1.90%
Commitment fee percentage |  |  |  |  | 0.375% |  |  |  |  |
Write-off of deferred financing costs |  |  | $ 0 | 0 | $ 1,800,000 | 500,000 |  |  |  |
Line of Credit [Member] | Revolving Credit Facility [Member] | Other Assets [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Deferred financing costs |  | $ 5,500,000 | 5,500,000 |  | 5,500,000 |  |  |  |  |
Line of Credit [Member] | Revolving Credit Facility [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit facility, amount outstanding |  | 195,000,000 | 195,000,000 |  | 195,000,000 |  |  |  |  |
Senior Unsecured Debt [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Amount of debt extinguished | $ 362,400,000 |  |  |  |  |  |  |  |  |
Repurchase of senior unsecured debt | 371,400,000 |  |  |  | 64,500,000 |  |  |  |  |
Debt issuance costs |  | $ 29,500,000 | $ 29,500,000 |  | $ 29,500,000 |  |  |  |  | $ 35,416,000
Senior Unsecured Debt [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 6.50% | 6.50% |  | 6.50% |  |  |  |  |
Senior Unsecured Debt [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 7.25% | 7.25% |  | 7.25% |  |  |  |  |
Senior Unsecured Debt [Member] | Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Unsecured debt |  | $ 1,753,000,000 | $ 1,753,000,000 |  | $ 1,753,000,000 |  |  |  |  |
Senior Unsecured Debt [Member] | Notes [Member] | Long-term Debt [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt discount |  | 92,900,000 | 92,900,000 |  | 92,900,000 |  |  |  |  |
Deferred financing costs |  | $ 29,500,000 | $ 29,500,000 |  | $ 29,500,000 |  |  |  |  |
Senior Unsecured Debt [Member] | 7.25% senior unsecured notes due February 1, 2019 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 7.25% | 7.25% |  | 7.25% |  |  |  |  |
Debt redemption price (percent) |  |  |  |  | 101.813% |  |  |  |  |
Amount of debt extinguished | 344,700,000 |  |  |  | $ 1,000,000 |  |  |  |  |
Senior Unsecured Debt [Member] | 6.5% senior unsecured notes due November 1, 2021 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 6.50% | 6.50% |  | 6.50% |  |  |  |  |
Amount of debt extinguished | 2,200,000 |  |  |  | $ 2,300,000 |  |  |  |  |
Senior Unsecured Debt [Member] | 6.875% senior unsecured notes due March 15, 2022 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 6.875% | 6.875% |  | 6.875% |  |  |  |  |
Amount of debt extinguished | 3,400,000 |  |  |  | $ 59,500,000 |  |  |  |  |
Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 2.625% | 2.625% |  | 2.625% |  |  |  |  |
Debt issued |  | $ 300,000,000.0 | $ 300,000,000.0 |  | $ 300,000,000.0 |  |  |  |  |
Proceeds from convertible Debt |  | $ 291,900,000 |  |  |  |  |  |  |  |
Debt conversion rate per $1000 principal (in shares per $1000) |  | 76.3650 |  |  |  |  |  |  |  |
Debt conversion price (in dollars per share) | $ / shares |  | $ 13.10 | $ 13.10 |  | $ 13.10 |  |  |  |  |
Debt instrument effective interest rate (percent) |  | 8.97% | 8.97% |  | 8.97% |  |  |  |  |
Estimated fair value of debt |  |  |  |  |  |  | $ 206,800,000 |  |  |
Debt discount |  | $ 92,877,000 | $ 92,877,000 |  | $ 92,877,000 |  | $ 93,200,000 |  |  | $ 0
Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] | Long-term Debt [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt issuance costs |  | 5,400,000 | 5,400,000 |  | 5,400,000 |  |  |  |  |
Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] | Additional Paid-in-Capital [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt issuance costs |  | $ 2,400,000 | $ 2,400,000 |  | $ 2,400,000 |  |  |  |  |
Senior Unsecured Debt [Member] | 6.875% senior unsecured notes due January 15, 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 6.875% | 6.875% |  | 6.875% |  |  |  |  |
Amount of debt extinguished | $ 12,100,000 |  |  |  | $ 21,800,000 |  |  |  |  |
Senior Unsecured Debt [Member] | Purchased Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Amount of debt extinguished |  |  |  |  | 84,600,000 |  |  |  |  |
Gain (loss) on extinguishment of debt |  |  | $ (13,800,000) |  | 4,900,000 |  |  |  |  |
Senior Unsecured Debt [Member] | Purchased Notes [Member] | Gain of Extinguishment of Debt [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Write-off of deferred financing costs |  |  | $ 5,300,000 | $ 0 | $ 6,300,000 | $ 0 |  |  |  |
Debt Conversion Scenario 1 [Member] | Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Number of trading days | day |  | 20 |  |  |  |  |  |  |  |
Number of consecutive trading days |  | 30 days |  |  |  |  |  |  |  |
Stock price relative to conversion price (percent) |  | 130.00% |  |  |  |  |  |  |  |
Debt Conversion Scenario 2 [Member] | Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Number of trading days | day |  | 5 |  |  |  |  |  |  |  |
Number of consecutive trading days |  | 5 days |  |  |  |  |  |  |  |
Stock price relative to product of sale price and conversion rate (percent) |  | 98.00% |  |  |  |  |  |  |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
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- Definition The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination. + References No definition available. + Details
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- Definition The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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