v3.10.0.1

Acquisition of Tanker Investments Ltd. (Details) $ / shares in Units, $ in Thousands |  |  | 9 Months Ended
--- | --- | --- | ---
Nov. 27, 2017 USD ($) vessel $ / shares shares | May 31, 2017 shares | Sep. 30, 2018 USD ($) | Sep. 30, 2017 USD ($)
Business Acquisition [Line Items] |  |  |  |
Proceeds from issuance of Class A common stock (note 12) |  |  | $ 0 | $ 5,000
Tanker Investments Ltd. |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Number of shares acquiring (in shares) | shares |  | 27,000,000 |  |
Proceeds from issuance of Class A common stock (note 12) | $ 151,300 |  |  |
Business acquisition, share price (USD per share) | $ / shares | $ 1.70 |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, liabilities, excluding banking debt | $ 47,100 |  |  |
Secured debt | 338,900 |  |  |
Business acquisition, transaction costs | $ 6,900 |  |  |
Ownership percentage | 11.30% |  |  |
Business combination, step acquisition, equity interest in acquiree, fair value | $ 19,200 |  |  |
Business combination, consideration transferred, including equity interest in acquiree held prior to combination | 177,400 |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, noncurrent liabilities, long-term debt | 337,100 |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, property, plant, and equipment | 467,200 |  |  |
Business combination, recognized identifiable assets acquired and liabilities assumed, operating lease | $ 200 |  |  |
Tanker Investments Ltd. | Class A |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Share for share exchange (in shares) | shares |  | 3.3 |  |
Number of shares issued (in shares) | shares | 88,977,544 |  |  |
Suezmax Tankers | Tanker Investments Ltd. |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Number of vessels | vessel | 10 |  |  |
Aframax Tanker | Tanker Investments Ltd. |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Number of vessels | vessel | 6 |  |  |
Long Range 2 | Tanker Investments Ltd. |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Number of vessels | vessel | 2 |  |  |
Vessels | Tanker Investments Ltd. |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business combination, average age of acquired property | 7 years 3 months 19 days |  |  |

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