Unaudited Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions |
Sep. 30, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Accounts receivable, related parties, current | $ 0.2 | $ 0.8 |
| Accumulated depreciation on vessels and equipment | 550.1 | 512.0 |
| Accumulated depreciation on vessels related to capital leases | 38.7 | 25.4 |
| Accumulated amortization on intangible assets | $ 10.2 | $ 8.2 |
| Common stock, shares authorized (in shares) | 585,000,000.0 | 385,000,000 |
| Class A | ||
| Common stock, shares authorized (in shares) | 485,000,000 | 285,000,000 |
| Common stock, shares issued (in shares) | 231,600,000 | 231,200,000 |
| Common stock, shares outstanding (in shares) | 231,600,000 | 231,200,000 |
| Class B | ||
| Common stock, shares authorized (in shares) | 100,000,000 | 100,000,000 |
| Common stock, shares issued (in shares) | 37,000,000 | 37,000,000 |
| Common stock, shares outstanding (in shares) | 37,000,000 | 37,000,000 |
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- Definition Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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