v3.10.0.1

Investments in and Advances to Equity Accounted Investments - Additional Information (Details) $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Nov. 27, 2017 USD ($) | May 31, 2017 USD ($) pool shares | Jan. 31, 2014 USD ($) member shares | Jun. 30, 2017 USD ($) | Sep. 30, 2018 USD ($) vessel | Dec. 31, 2017 USD ($) | Aug. 31, 2014
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Total principal |  |  |  |  | $ 814,709 | $ 963,247 |
Tanker Investments Ltd. |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Ownership percentage | 11.30% |  |  |  |  |  |
Number of shares acquiring (in shares) | shares |  | 27,000,000 |  |  |  |  |
Class A | Tanker Investments Ltd. |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Share for share exchange (in shares) | shares |  | 3.3 |  |  |  |  |
Entities Under Common Control | Teekay Tanker Operations Limited |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Purchase price of acquisition |  | $ 39,000 |  |  |  |  |
Original ownership interest percentage |  | 50.00% |  |  |  |  | 50.00%
Entities Under Common Control | Teekay Tanker Operations Limited | Working Capital |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Purchase price of acquisition |  | $ 13,100 |  |  |  |  |
High-Q Joint Venture |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Ownership percentage |  |  |  |  | 50.00% |  |
Tanker Investments Ltd. |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Number of shares acquiring (in shares) | shares |  | 27,000,000 |  |  |  |  |
High-Q Joint Venture |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Number of vessels | vessel |  |  |  |  | 1 |  |
Total principal |  |  |  |  | $ 38,700 | $ 42,700 |
Percentage of exposure to loan guarantee |  |  |  |  | 50.00% |  |
High-Q Joint Venture | Joint Venture Interest Rate Derivative |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Fixed interest rate |  |  |  |  | 1.47% |  |
Tanker Investments Ltd. |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Ownership percentage |  | 11.30% |  |  |  |  |
Investment in equity accounted investment |  |  | $ 25,000 |  |  |  |
Number of board members to elect | member |  |  | 1 |  |  |  |
Tanker Investments Ltd. | Maximum |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Number of shares available through exercise of stock purchase warrant (in shares) | shares |  |  | 750,000 |  |  |  |
Tanker Investments Ltd. | Common Stock |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Common stock, shares purchased (in shares) | shares |  |  | 2,500,000.0 |  |  |  |
Tanker Investments Ltd. | Preferred Stock |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Common stock, shares purchased (in shares) | shares |  |  | 1 |  |  |  |
Teekay Tanker Operations Limited |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Number of commercially managed tanker pools | pool |  | 4 |  |  |  |  |
Original ownership interest percentage |  | 50.00% |  |  |  |  |
Teekay Tanker Operations Limited | TTOL |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Equity method investment, remaining ownership percentage |  | 50.00% |  |  |  |  |
Tanker Investments Ltd. |  |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |  |
Investment write down |  |  |  | $ 28,100 |  |  |
Equity method investment, realized gain (loss) on disposal | $ 1,400 |  |  |  |  |  |

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