Long-term Debt - Additional Information (Details) $ / shares in Units, shares in Millions |
12 Months Ended | |
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Dec. 31, 2018
USD ($)
$ / shares
shares
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Dec. 31, 2017
USD ($)
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| Debt Instrument [Line Items] | ||
| Principal, net of issuance costs | $ 835,000,000 | $ 1,211,000,000 |
| Convertible Notes Payable [Member] | 4.125% Convertible Senior Notes Due September 1, 2022 [Member] | ||
| Debt Instrument [Line Items] | ||
| Principal | 150,000,000 | $ 150,000,000 |
| Principal, net of issuance costs | $ 145,000,000 | |
| Interest rate | 4.125% | |
| Conversion rate of shares for each $1,000 principal amount of convertible notes | 36.7107 | |
| Conversion of debt equals shares (in shares) | shares | 5.5 | |
| Conversion price per share (in usd per share) | $ / shares | $ 27.24 | |
| Adjustment for dividends declared (in usd per share) | $ / shares | $ 0.33 | |
| Redemption price, percentage | 100.00% |
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- Definition Adjustment for dividends declared minimum. No definition available.
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- Definition The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The price per share of the conversion feature embedded in the debt instrument. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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