Document_and_Entity_Informatio
| Document and Entity Information | 6 Months Ended |
| Jun. 30, 2013 | |
| Document Information [Line Items] | ' |
| Document Type | '6-K |
| Amendment Flag | 'false |
| Document Period End Date | 30-Jun-13 |
| Document Fiscal Year Focus | '2013 |
| Document Fiscal Period Focus | 'Q2 |
| Trading Symbol | 'TNK |
| Entity Registrant Name | 'TEEKAY TANKERS LTD. |
| Entity Central Index Key | '0001419945 |
| Current Fiscal Year End Date | '--12-31 |
CONSOLIDATED_STATEMENTS_OF_LOS
| CONSOLIDATED STATEMENTS OF (LOSS) INCOME (USD $) | 3 Months Ended | 6 Months Ended | ||
| In Thousands, except Share data, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 |
| REVENUES | ' | ' | ' | ' |
| Time charter revenues (note 8a) | $22,710 | $32,032 | $46,888 | $67,669 |
| Net pool revenues from affiliates (note 8a) | 15,493 | 16,136 | 31,591 | 32,449 |
| Voyage charter revenue | 2,433 | ' | 4,283 | ' |
| Interest income from investment in term loans | 2,856 | 2,872 | 5,683 | 5,734 |
| Total revenues | 43,492 | 51,040 | 88,445 | 105,852 |
| OPERATING EXPENSES | ' | ' | ' | ' |
| Voyage expenses (note 8a) | 2,449 | 107 | 5,362 | 1,429 |
| Vessel operating expenses (note 8a) | 24,832 | 23,002 | 47,886 | 46,223 |
| Time-charter hire expense | 1,951 | 644 | 3,937 | 2,305 |
| Depreciation and amortization | 11,921 | 18,047 | 23,785 | 36,038 |
| General and administrative (note 8a) | 3,362 | 2,322 | 6,923 | 3,660 |
| Loss provision on investment in term loans (note 2) | 4,511 | ' | 4,511 | ' |
| Loss on sale of vessel and equipment (note 9) | ' | ' | 71 | ' |
| Total operating expenses | 49,026 | 44,122 | 92,475 | 89,655 |
| (Loss) income from operations | -5,534 | 6,918 | -4,030 | 16,197 |
| OTHER ITEMS | ' | ' | ' | ' |
| Interest expense | -2,604 | -6,654 | -5,115 | -14,215 |
| Interest income | 20 | 11 | 24 | 21 |
| Realized and unrealized gain (loss) on derivative instruments (note 5) | 2,748 | -3,895 | 1,982 | -4,974 |
| Other expenses | -354 | -703 | -538 | -979 |
| Total other items | -190 | -11,241 | -3,647 | -20,147 |
| Net loss | -5,724 | -4,323 | -7,677 | -3,950 |
| Add: Net loss attributable to the Dropdown Predecessor (note 8c) | ' | 5,398 | ' | 9,163 |
| Net (loss) income attributable to common stockholders | ($5,724) | $1,075 | ($7,677) | $5,213 |
| Per common share amounts | ' | ' | ' | ' |
| • Basic (loss) earnings attributable to stockholders of Teekay Tankers | ($0.07) | $0.01 | ($0.09) | $0.07 |
| • Diluted (loss) earnings attributable to stockholders of Teekay Tankers | ($0.07) | $0.01 | ($0.09) | $0.07 |
| Cash dividends declared | $0.03 | $0.11 | $0.06 | $0.27 |
| Weighted-average number of Class A and Class B common shares outstanding | ' | ' | ' | ' |
| • Basic | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 |
| • Diluted | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 |
CONSOLIDATED_BALANCE_SHEETS
| CONSOLIDATED BALANCE SHEETS (USD $) | Jun. 30, 2013 | Dec. 31, 2012 |
| In Thousands, unless otherwise specified | ||
| Current | ' | ' |
| Cash and cash equivalents | $37,708 | $26,341 |
| Pool receivable from affiliates, net (note 8b) | 7,481 | 9,101 |
| Accounts receivable | 7,633 | 4,523 |
| Interest receivable on investment in term loans | ' | ' |
| Vessel held for sale (note 9) | ' | 9,114 |
| Due from affiliates (note 8b) | 20,981 | 24,787 |
| Prepaid expenses | 8,077 | 9,714 |
| Investment in term loans (note 2) | 122,841 | 119,385 |
| Total current assets | 204,721 | 202,965 |
| Vessels and equipment | ' | ' |
| At cost, less accumulated depreciation of $227.4 million (2012-$203.6 million) | 867,035 | 885,992 |
| Loan to joint venture (note 3) | 9,830 | 9,830 |
| Investment in joint venture (note 3) | 7,289 | 3,457 |
| Other non-current assets | 2,958 | 3,412 |
| Total assets | 1,091,833 | 1,105,656 |
| Current | ' | ' |
| Accounts payable | 2,098 | 3,346 |
| Accrued liabilities | 14,543 | 17,882 |
| Current portion of long-term debt (note 4) | 25,246 | 25,246 |
| Current portion of derivative instruments (note 5) | 7,184 | 7,200 |
| Deferred revenue | 1,302 | 4,564 |
| Due to affiliates (note 8b) | 22,375 | 3,592 |
| Total current liabilities | 72,748 | 61,830 |
| Long-term debt (note 4) | 704,968 | 710,455 |
| Derivative instruments (note 5) | 19,540 | 26,431 |
| Other long-term debt | 4,902 | 4,757 |
| Total liabilities | 802,158 | 803,473 |
| Commitments and contingencies (note 3, 5 and 11) | ' | ' |
| Equity | ' | ' |
| Common stock and additional paid-in capital (300 million shares authorized, 71.1 million class A and 12.5 million Class B shares issued and outstanding as of June 30, 2013 and December 31, 2012 (note 7) | 672,744 | 672,560 |
| Accumulated deficit | -383,069 | -370,377 |
| Total equity | 289,675 | 302,183 |
| Total liabilities and equity | $1,091,833 | $1,105,656 |
CONSOLIDATED_BALANCE_SHEETS_Pa
| CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) | Jun. 30, 2013 | Dec. 31, 2012 |
| In Millions, unless otherwise specified | ||
| Accumulated depreciation on vessels | $227.40 | $203.60 |
| Common stock, shares authorized | 300 | 300 |
| Class A [Member] | ' | ' |
| Common stock, shares issued | 71.1 | 71.1 |
| Common stock, shares outstanding | 71.1 | 71.1 |
| Class B [Member] | ' | ' |
| Common stock, shares issued | 12.5 | 12.5 |
| Common stock, shares outstanding | 12.5 | 12.5 |
CONSOLIDATED_STATEMENTS_OF_CAS
| CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) | 6 Months Ended | |
| In Thousands, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 |
| OPERATING ACTIVITIES | ' | ' |
| Net loss | ($7,677) | ($3,950) |
| Non-cash items: | ' | ' |
| Loss provision on investment in term loans | 4,511 | ' |
| Depreciation and amortization | 23,785 | 36,038 |
| Unrealized (gain) loss on derivative instruments | -6,907 | 259 |
| Other | 973 | 592 |
| Change in operating assets and liabilities | 6,969 | -24,539 |
| Expenditures for dry docking | -3,696 | ' |
| Net operating cash flow | 17,958 | 8,400 |
| FINANCING ACTIVITIES | ' | ' |
| Proceeds from long-term debt | 27,136 | 5,000 |
| Repayments of long-term debt | -12,623 | -900 |
| Prepayment of long-term debt | -20,000 | -55,000 |
| Proceeds from long-term debt of Dropdown Predecessor | ' | 2,312 |
| Repayments of long-term debt of Dropdown Predecessor | ' | -10,372 |
| Prepayment of long-term debt of Dropdown Predecessor | ' | -15,000 |
| Acquisition of 13 vessels from Teekay Corporation | ' | -1,078 |
| Net advances from affiliates | ' | 16,913 |
| Contribution of capital from Teekay Corporation | ' | 9,728 |
| Proceeds from issuance of Class A common stock | ' | 69,000 |
| Share issuance costs | ' | -3,217 |
| Cash dividends paid | -5,015 | -21,364 |
| Net financing cash flow | -10,502 | -3,978 |
| INVESTING ACTIVITIES | ' | ' |
| Proceeds from sale of vessel and equipment | 9,119 | ' |
| Expenditures for vessels and equipment | -1,208 | -1,399 |
| Investment in joint venture | -4,000 | -3,035 |
| Net investing cash flow | 3,911 | -4,434 |
| Increase (decrease) in cash and cash equivalents | 11,367 | -12 |
| Cash and cash equivalents, beginning of the period | 26,341 | 18,566 |
| Cash and cash equivalents, end of the period | $37,708 | $18,554 |
CONSOLIDATED_STATEMENTS_OF_CHA
| CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) | Total | Common Stock and Additional Paid-in Capital [Member] | Accumulated Deficit [Member] | Class A [Member] | Class B [Member] |
| In Thousands, except Share data | USD ($) | USD ($) | Common Stock and Additional Paid-in Capital [Member] | Common Stock and Additional Paid-in Capital [Member] | |
| USD ($) | USD ($) | ||||
| Balance at Dec. 31, 2012 | $302,183 | ' | ($370,377) | $672,435 | $125 |
| Balance, shares at Dec. 31, 2012 | ' | 83,591 | ' | ' | ' |
| Net loss | -7,677 | ' | -7,677 | ' | ' |
| Dividends declared | -5,015 | ' | -5,015 | ' | ' |
| Equity-based compensation (note 7) | 184 | ' | ' | 184 | ' |
| Ending balance at Jun. 30, 2013 | $289,675 | ' | ($383,069) | $672,619 | $125 |
| Balance, shares at Jun. 30, 2013 | ' | 83,591 | ' | ' | ' |
Basis_of_Presentation
| Basis of Presentation | 6 Months Ended | |
| Jun. 30, 2013 | ||
| Basis of Presentation | ' | |
| 1 | Basis of Presentation | |
| The unaudited interim consolidated financial statements have been prepared in conformity with United States generally accepted accounting principles (or GAAP). These financial statements include the accounts of Teekay Tankers Ltd. and its wholly-owned subsidiaries (collectively the Company). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. | ||
| Certain information and footnote disclosures required by GAAP for complete annual financial statements have been omitted and, therefore, these interim financial statements should be read in conjunction with the Company’s audited consolidated financial statements filed on Form 20-F for the year ended December 31, 2012. In the opinion of management, these interim unaudited consolidated financial statements reflect all adjustments, consisting solely of a normal recurring nature, necessary to present fairly, in all material respects, the Company’s consolidated financial position, results of operations, and cash flows for the interim periods presented. The results of operations for the interim periods presented are not necessarily indicative of those for a full fiscal year. Significant intercompany balances and transactions have been eliminated upon consolidation. | ||
| In order to more closely align the Company’s presentation to that of many of its peers, the cost of ship management activities of $1.4 million and $2.9 million for the three and six months ended June 30, 2013 have been presented in vessel operating expenses. Prior to 2013, the Company included these amounts in general and administrative expenses. All such costs incurred in comparative periods have been reclassified from general and administrative expenses to vessel operating expenses to conform to the presentation adopted in the current period. The amounts reclassified were $2.1 million and $4.2 million for the three and six months ended June 30, 2012. | ||
| The acquisition of 13 conventional oil tankers from Teekay Corporation (or “Teekay”) in June 2012 (or the “2012 Acquired Business”), has been accounted for as an acquisition of interests in vessels from Teekay as a transfer of the business between entities under common control. Under this method, the carrying amount of net assets recognized in the balance sheets of each combining entity are carried forward to the balance sheet of the Company at Teekay’s historical cost is accounted for as an equity distribution to Teekay. In addition, transfers of net assets between entities under common control are accounted for as if the transfer occurred from the date that the Company and the acquired vessels were both under the common control of Teekay and had begun operations. As a result, the Company’s financial statements prior to the date the interests in these vessels were actually acquired by the Company are retroactively adjusted to include the results of these vessels and their related operations and cash flows (referred to herein collectively as the Dropdown Predecessor) during the periods they were under common control of Teekay and had begun operations. | ||
| The acquisition of the 2012 Acquired Business was accounted for as reorganization between entities under common control. As a result, the Company’s consolidated financial statements for the three and six months ended June 30, 2012, reflect the 2012 Acquired Business as if the Company had acquired the 2012 Acquired Business when the 13 vessels began their respective operations under the ownership of Teekay. For more information about this acquisition, please refer to the Company’s audited consolidated financial statements filed on Form 20-F for the year ended December 31, 2012. | ||
Investment_in_Term_Loans
| Investment in Term Loans | 6 Months Ended | |
| Jun. 30, 2013 | ||
| Investment in Term Loans | ' | |
| 2 | Investment in Term Loans | |
| In July 2010, the Company invested in two term loans with a total principal amount outstanding of $115.0 million for a total cost of $115.6 million (the Loans) which matured in July 2013. The loans are secured by first priority mortgages registered on two 2010-built Very Large Crude Carriers (or VLCCs). The Loans had an annual interest rate of 9% per annum and include a repayment premium feature that provided a total investment yield of approximately 10% per annum. As at June 30, 2013 and December 31, 2012, $6.6 million and $1.6 million, respectively, were recorded as accrued interest income from the investment in these term loans, and have been reclassified from interest receivable to investment in term loans on the consolidated balance sheets as at June 30, 2013 and December 31, 2012. The 9% interest income was payable in quarterly installments. The principal amount of the Loans and repayment premium were payable in full at maturity in July 2013. As at June 30, 2013 and December 31, 2012, the repayment premium included in the investment in term loans balance was $3.3 million and $2.7 million, respectively. Interest income in respect of the Loans is included in revenues in the consolidated statements of (loss) income. | ||
| The borrowers under the Loans have been in default on their interest payment obligations since January 2013 and subsequently, in default on the repayment of the loan principal as the loans matured in July 2013. In May 2013, the Company took over management of the vessels. Currently, one of the vessels is trading in the spot tanker market under the Company’s management while the other vessel remains under detention by authorities in Egypt due to an incident that occurred prior to the transition of vessel management to the Company. The vessel’s insurers are in the process of negotiating the release of the vessel, after which it is expected the vessel will commence trading in the spot tanker market under the Company’s management. The Company recorded a $4.5 million loss provision in respect of the investment in terms loans inclusive of $6.6 million of accrued but unpaid interest as at June 30, 2013, to reflect the estimated loss that could be incurred based on the Company’s current estimates of amounts recoverable from future operating cash flows of the vessels and the net proceeds from the sale of the two VLCC vessels. | ||
Investment_in_Joint_Venture
| Investment in Joint Venture | 6 Months Ended | |
| Jun. 30, 2013 | ||
| Investment in Joint Venture | ' | |
| 3 | Investment in Joint Venture | |
| The Company has a joint venture arrangement with Wah Kwong Maritime Transport Holdings Limited (or Wah Kwong). The Company has a 50% economic interest in the joint venture, which is jointly controlled by the Company and Wah Kwong. A VLCC jointly owned by the Company and its joint venture partner, the Hong Kong Spirit, was delivered on June 14, 2013 and commenced its five-year time-charter-out contract shortly thereafter, where it earns a fixed daily rate and an additional amount if the daily rate of any sub-charter earned by the unrelated party exceeds a certain threshold. The Company records its portion of equity (loss) income in other expenses in the consolidated statements of (loss) income. The equity losses recognized for the three and six months ended June 30, 2013 were $0.2 million and $0.2 million, respectively. | ||
| As of June 30, 2013, the joint venture had a loan from a financial institution of $68.6 million, which is repayable in 32 quarterly installments of $1.4 million each commencing three months after delivery of the vessel and a balloon payment of $22.6 million at its maturity. The loan is secured by a first-priority statutory mortgage on the VLCC and guaranteed by both the Company and Wah Kwong. The Company’s exposure on this loan is limited to its 50% guarantee of the loan. In addition, the joint venture also entered into an interest rate swap agreement for the full notional amount of the loan fixed at a rate of 1.47% that requires quarterly payments in March, June, September and December until June 2018. | ||
| As at June 30, 2013, the carrying value of the Company’s investment in the joint venture was $7.3 million and the Company had also advanced an additional $9.8 million to the joint venture in the form of a non-interest bearing and unsecured loan. | ||
LongTerm_Debt
| Long-Term Debt | 6 Months Ended | ||||||||
| Jun. 30, 2013 | |||||||||
| Long-Term Debt | ' | ||||||||
| 4 | Long-Term Debt | ||||||||
| June 30, | December 31, | ||||||||
| 2013 | 2012 | ||||||||
| $ | $ | ||||||||
| Revolving Credit Facilities due through 2018 | 558,032 | 555,472 | |||||||
| Term Loans due through 2021 | 172,182 | 180,229 | |||||||
| 730,214 | 735,701 | ||||||||
| Less current portion | (25,246 | ) | (25,246 | ) | |||||
| Total | 704,968 | 710,455 | |||||||
| As at June 30, 2013, the Company had three revolving credit facilities (or the Revolvers), which provided for aggregate borrowings of up to $775.8 million, of which $217.8 million was undrawn. Interest payments are based on LIBOR plus margins, which at June 30, 2013, ranged between 0.45% and 0.60% (December 31, 2012: 0.45% and 0.60%). The total amount available under the Revolvers reduces by $47.0 million (remainder of 2013), $94.0 million (2014), $120.9 million (2015), $89.1 million (2016), $395.9 million (2017) and $28.9 million thereafter. As at June 30, 2013, the Revolvers are collateralized by 21 of the Company’s vessels, together with other related security. One of the Revolvers requires that the Company’s applicable subsidiary maintain a minimum hull coverage ratio of 105% of the total outstanding drawn balance for the facility period. As at June 30, 2013, this ratio was 114%. The vessel value used in this ratio is an appraised value prepared by the Company based on second-hand sale and purchase market data. A further delay in the recovery of the tanker market could negatively affect the ratio. In addition, one of the Revolvers requires the Company and certain of its subsidiaries to maintain a minimum liquidity (cash, cash equivalents and undrawn committed revolving credit lines with at least six months to maturity) of $35.0 million and at least 5.0% of the Company’s total debt. The remaining two Revolvers are guaranteed by Teekay and contain covenants that require Teekay to maintain the greater of free cash (cash and cash equivalents) of at least $100.0 million and an aggregate of free cash and undrawn committed revolving credit lines with at least six months to maturity of at least 7.5% of Teekay’s total consolidated debt which has recourse to Teekay. As at June 30, 2013, the Company and Teekay were in compliance with all their covenants in respect of the Revolvers. | |||||||||
| As at June 30, 2013, the Company had three term loans outstanding, which totaled $172.2 million (December 31, 2012—$180.2 million). Interest payments on the term loans are based on a combination of fixed and variable rates where fixed rates range from 4.06% to 4.90% and variable rates are based on LIBOR plus a margin. At June 30, 2013, the margins ranged from 0.30% to 1.0% (December 31, 2012: 0.30% to 1.0%). The term loan repayments are made in quarterly or semi-annual payments and two of the term loans have balloon or bullet repayments due at maturity in 2019 and 2021. The term loans are collateralized by first-priority mortgages on six of the Company’s vessels, together with certain other related security. Two of the term loans require that the Company’s subsidiaries maintain a minimum hull coverage ratio of 120% of the total outstanding balance for the facility period. As at June 30, 2013, the loan to value ratios were 127% and 311%, respectively. The vessel values used in this ratio are appraised values prepared by the Company based on second-hand sale and purchase market data. A further delay in the recovery of the tanker market could negatively affect the ratio. The term loans are guaranteed by Teekay and contain covenants that require Teekay to maintain the greater of free cash (cash and cash equivalents) of at least $100.0 million and an aggregate of free cash and undrawn committed revolving credit lines with at least six months to maturity of at least 7.5% of Teekay’s total consolidated debt which has recourse to Teekay. As at June 30, 2013, the Company and Teekay were in compliance with all their covenants in respect of these term loans. | |||||||||
| The weighted-average effective interest rate on the Company’s long-term debt as at June 30, 2013, was 1.2% (December 31, 2012 – 1.2%). This rate does not reflect the effect of the Company’s interest rate swap agreements (see Note 5). | |||||||||
| The aggregate annual long-term principal repayments required to be made by the Company under the Revolvers and term loans subsequent to June 30, 2013 are $12.6 million (remaining 2013), $25.2 million (2014), $58.5 million (2015), $108.1 million (2016), $415.3 million (2017) and $110.5 million (thereafter). | |||||||||
Derivative_Instruments
| Derivative Instruments | 6 Months Ended | ||||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||||
| Derivative Instruments | ' | ||||||||||||||||||
| 5 | Derivative Instruments | ||||||||||||||||||
| The Company uses derivatives in accordance with its overall risk management policies. The Company enters into interest rate swap agreements which exchange a receipt of floating interest for a payment of fixed interest to reduce the Company’s exposure to interest rate variability on its outstanding floating-rate debt. The Company has not designated, for accounting purposes, its interest rate swaps as cash flow hedges of its U.S. Dollar LIBOR-denominated borrowings. | |||||||||||||||||||
| Realized and unrealized gains (losses) relating to the Company’s interest rate swaps have been reported in realized and unrealized gain (loss) on non-designated derivative instruments in the consolidated statements of (loss) income. During the three and six months ended June 30, 2013, the Company recognized realized losses of $2.5 million and $4.9 million and unrealized gains of $5.3 million and $6.9 million, respectively, relating to its interest rate swaps. During the three and six months ended June 30, 2012, the Company recognized realized losses of $2.4 million and $4.8 million and unrealized losses of $1.5 million and $0.2 million, respectively, relating to its interest rate swaps. | |||||||||||||||||||
| The following summarizes the Company’s derivative positions as at June 30, 2013: | |||||||||||||||||||
| Fair | |||||||||||||||||||
| Value / | |||||||||||||||||||
| Carrying | |||||||||||||||||||
| Amount | |||||||||||||||||||
| of Asset | |||||||||||||||||||
| (Liability) | |||||||||||||||||||
| Interest Rate Index | $ | $ | (years) | (%) (1) | |||||||||||||||
| LIBOR-Based Debt: | |||||||||||||||||||
| U.S. Dollar-denominated interest rate swap | USD LIBOR 3 month | 200,000 | (9,871 | ) | 3.3 | 2.61 | |||||||||||||
| U.S. Dollar-denominated interest rate swap | USD LIBOR 3 month | 100,000 | (16,848 | ) | 4.3 | 5.55 | |||||||||||||
| U.S. Dollar-denominated interest rate swap | USD LIBOR 3 month | 45,000 | (6 | ) | 0.1 | 1.19 | |||||||||||||
| -1 | Excludes the margin the Company pays on its variable-rate debt, which as of June 30, 2013 ranged from 0.3% to 1.0%. | ||||||||||||||||||
| The Company is potentially exposed to credit loss in the event of non-performance by the counterparty to the interest rate swap agreements. In order to minimize counterparty risk, the Company only enters into derivative transactions with counterparties that are rated A- or better by Standard & Poor’s or A3 or better by Moody’s at the time transactions are entered into. | |||||||||||||||||||
| As at June 30, 2013, the Company had several interest rate swaps with the same counterparty that are subject to the same master agreement, which provides for the net settlement of all swaps subject to the master agreement through a single payment in the event of default or termination of any one swap. The fair value of these interest rate swaps are presented on a gross basis in the Company’s consolidated balance sheets. As at June 30, 2013, these interest rate swaps had an aggregate fair value liability amount of $11.0 million. | |||||||||||||||||||
Financial_Instruments
| Financial Instruments | 6 Months Ended | ||||||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||||||
| Financial Instruments | ' | ||||||||||||||||||||
| 6 | Financial Instruments | ||||||||||||||||||||
| a) | Fair Value Measurements | ||||||||||||||||||||
| For a description of how the Company estimates fair value and for a description of the fair value hierarchy levels, see Note 12 to the Company’s audited consolidated financial statements filed with its Annual Report on the Form 20-F for the year ended December 31, 2012. The following table includes the estimated fair value and carrying value of those assets and liabilities that are measured at fair value on a recurring and non-recurring basis as well as the estimated fair value of the Company’s financial instruments that are not accounted for at the fair value on a recurring basis. | |||||||||||||||||||||
| June 30, 2013 | December 31, 2012 | ||||||||||||||||||||
| Fair | Carrying | Fair | Carrying | Fair | |||||||||||||||||
| Value | Amount | Value | Amount | Value | |||||||||||||||||
| Hierarchy | Asset / | Asset / | Asset / | Asset / | |||||||||||||||||
| Level | (Liability) | (Liability) | (Liability) | (Liability) | |||||||||||||||||
| $ | $ | $ | $ | ||||||||||||||||||
| Recurring: | |||||||||||||||||||||
| Cash and cash equivalents | Level 1 | 37,708 | 37,708 | 26,341 | 26,341 | ||||||||||||||||
| Derivative instruments | |||||||||||||||||||||
| Interest rate swap agreements | Level 2 | (26,724 | ) | (26,724 | ) | (33,631 | ) | (33,631 | ) | ||||||||||||
| Non-Recurring: | |||||||||||||||||||||
| Vessels and equipment | Level 2 | — | — | 252,068 | 252,068 | ||||||||||||||||
| Vessel held for sale (note 9) | Level 2 | — | — | 9,114 | 9,114 | ||||||||||||||||
| Other: | |||||||||||||||||||||
| Investment in term loans and interest receivable | Level 3 | 122,841 | 119,929 | 119,385 | 117,784 | ||||||||||||||||
| Loan to joint venture | Note (1) | 9,830 | Note (1) | 9,830 | Note (1) | ||||||||||||||||
| Long-term debt, including current portion | Level 2 | (730,214 | ) | (654,674 | ) | (735,701 | ) | (648,724 | ) | ||||||||||||
| -1 | The Company’s loan to the joint venture, together with the Company’s equity investment in the joint venture form the aggregate carrying value of the Company’s interest in an entity accounted for by the equity method in these consolidated financial statements. The fair value of the individual components of such aggregate interest as at June 30, 2013 and December 31, 2012 was not determinable. | ||||||||||||||||||||
| b) | Financing Receivables | ||||||||||||||||||||
| The following table contains a summary of the Company’s financing receivables by type and the method by which the Company monitors the credit quality of its financing receivables on a quarterly basis. | |||||||||||||||||||||
| June 30, | December 31, | ||||||||||||||||||||
| 2013 | 2012 | ||||||||||||||||||||
| Class of Financing Receivable | Credit Quality Indicator | Grade | $ | $ | |||||||||||||||||
| Investment in term loans (see Note 2) | Collateral | Non-Performing | 122,841 | 119,385 | |||||||||||||||||
| Loan to joint venture | Other internal metrics | Performing | 9,830 | 9,830 | |||||||||||||||||
| 132,671 | 129,215 | ||||||||||||||||||||
StockBased_Compensation
| Stock-Based Compensation | 6 Months Ended | |
| Jun. 30, 2013 | ||
| Stock-Based Compensation | ' | |
| 7 | Stock-Based Compensation | |
| In March 2013, 142,157 Class A common shares, with an aggregate value of $0.4 million were granted to the Company’s non-management directors as part of their annual compensation for 2013. These Class A common shares were purchased on the open market and distributed to the directors. | ||
| The Company grants restricted stock units as incentive-based compensation under the Teekay Tankers Ltd. 2007 Long-Term Incentive Plan to certain employees of Teekay Corporation’s subsidiaries that provide services to the Company. The Company measures the cost of such awards using the grant date fair value of the award and recognizes that cost, net of estimated forfeitures, over the requisite service period. The requisite service period consists of the period from the grant date of the award to the earlier of the date of vesting or the date the recipient becomes eligible for retirement. For stock-based compensation awards subject to graded vesting, the Company calculates the value for the award as if it was one single award with one expected life and amortizes the calculated expense for the entire award on a straight-line basis over the requisite service period. The compensation cost of the Company‘s stock-based compensation awards is reflected in general and administrative in the Company’s consolidated statements of (loss) income. | ||
| During March 2013, the Company granted 411,629 restricted stock units with a grant date fair value of $1.0 million to certain employees of Teekay’s subsidiaries, which provide services to the Company, based on the Company’s closing share price on the grant date. Each restricted stock unit is equal in value to one share of the Company’s common shares plus reinvested distributions from the grant date to the vesting date. The restricted stock units vest equally over three years from the grant date. Any portion of a restricted stock unit award that is not vested on the date of a recipient’s termination of service is cancelled, unless their termination arises as a result of the recipient’s retirement and, in this case, the restricted stock unit award will continue to vest in accordance with the vesting schedule. Upon vesting, the value of the restricted stock unit awards is paid to each recipient in the form of common shares. During the three and six months ended June 30, 2013, the Company recorded an expense of $0.1 million and $0.2 million, respectively (2012—$nil) related to the restricted stock units. | ||
Related_Party_Transactions
| Related Party Transactions | 6 Months Ended | ||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||
| Related Party Transactions | ' | ||||||||||||||||
| 8 | Related Party Transactions | ||||||||||||||||
| a. | Teekay and its wholly-owned subsidiary and the Company’s manager, Teekay Tankers Management Services Ltd. (the Manager), provide commercial, technical, strategic and administrative services to the Company. In addition, certain of the Company’s vessels participate in pooling arrangements that are managed in whole or in part by subsidiaries of Teekay (collectively the Pool Managers). The Company also has chartered out tankers to Teekay. For additional information about these arrangements, please read “Item 7 – Major Shareholders and Related Party Transactions – Related Party Transactions – Pooling Agreements” in our Annual Report on From 20-F for the year ended December 31, 2012. Amounts paid by the Company for such related party transactions for the periods indicated were as follows: | ||||||||||||||||
| Three Months | Six Months Ended | ||||||||||||||||
| Ended | |||||||||||||||||
| June 30, | June 30, | June 30, | June 30, | ||||||||||||||
| 2013 | 2012 | 2013 | 2012 | ||||||||||||||
| $ | $ | $ | $ | ||||||||||||||
| Time-charter revenues (i) | 3,671 | 3,671 | 7,302 | 7,342 | |||||||||||||
| Pool management fees and commissions (ii) | 967 | 801 | 1,997 | 1,647 | |||||||||||||
| Commercial management fees (iii) | 264 | 204 | 570 | 421 | |||||||||||||
| Vessel operating expenses—crew training | 268 | 522 | 666 | 1,102 | |||||||||||||
| Vessel operating expenses—technical management fee (iv) | 1,412 | 2,080 | 2,859 | 4,152 | |||||||||||||
| General and administrative (v) | 2,717 | 1,041 | 5,446 | 2,017 | |||||||||||||
| General and administrative—Dropdown Predecessor | — | 1,697 | — | 2,958 | |||||||||||||
| Interest Expense—Dropdown Predecessor | — | 5,335 | — | 11,658 | |||||||||||||
| (i) | The Company chartered-out the Pinnacle Spirit and Summit Spirit to Teekay under fixed-rate time-charter contracts, which expire in 2014. | ||||||||||||||||
| (ii) | The Company’s share of the Pool Managers’ fees that are reflected as a reduction to net pool revenues from affiliates on the Company’s consolidated statements of (loss) income. | ||||||||||||||||
| (iii) | The Manager’s commercial management fees for vessels on time-charter out contracts, which are reflected in voyage expenses on the Company’s consolidated statements of (loss) income. | ||||||||||||||||
| (iv) | The cost of ship management services provided by the Manager of $1.4 million and $2.9 million for the three and six months ended June 30, 2013, respectively, have been presented as vessel operating expenses (see Note 1). The amount reclassified from general and administrative to vessel operating expenses in the comparable periods to conform to the presentation adopted in the current periods were $2.1 million and $4.2 million, respectively. | ||||||||||||||||
| (v) | The Manager’s strategic and administrative service fees. | ||||||||||||||||
| b. | The Manager and other subsidiaries of Teekay collect revenues and remit payments for expenses incurred by the Company’s vessels. Such amounts, which are presented on the Company’s consolidated balance sheets in due from affiliates or due to affiliates, are without interest or stated terms of repayment. In addition, $4.1 million and $4.9 million was payable to the Manager as at June 30, 2013 and December 31, 2012, respectively, for reimbursement of the Manager’s crewing and manning costs to operate the Company’s vessels and such amounts are included in due to affiliates on the consolidated balance sheets. The amounts owing from the Pool Managers for monthly distributions are reflected in the consolidated balance sheets as pool receivables from affiliates, are without interest and are repayable upon the terms contained within the applicable pool agreement. In addition, the Company had advanced $19.7 million and $16.6 million as at June 30, 2013 and December 31, 2012, respectively, to the Pool Managers for working capital purposes. These amounts, which are reflected in the consolidated balance sheets in due from affiliates, are without interest and are repayable when vessels leave the pools. | ||||||||||||||||
| c. | During June 2012, the Company acquired the 2012 Acquired Business from Teekay, which consisted of seven conventional oil tankers and six product tankers and related time-charter contracts, debt facilities and an interest rate swap, for an aggregate price of approximately $454.2 million, including the assumption of outstanding debt of approximately $428.1 million. Ten of the vessels were acquired on June 15, 2012 and the remaining three were acquired on June 26, 2012. As partial consideration for this acquisition, the Company issued to Teekay 4.5 million Class A common shares and made a cash payment of $1.1 million to Teekay. | ||||||||||||||||
Vessel_Sale
| Vessel Sale | 6 Months Ended | |
| Jun. 30, 2013 | ||
| Vessel Sale | ' | |
| 9 | Vessel Sale | |
| In January 2013, the Company completed the sale of the Aframax tanker, Nassau Spirit, for proceeds of $9.1 million. The vessel was classified as held for sale on the consolidated balance sheet as at December 31, 2012, when its net book value was written down to its sale proceeds net of cash outlays to complete the sale. | ||
Loss_Earnings_Per_Share
| (Loss) Earnings Per Share | 6 Months Ended | ||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||
| (Loss) Earnings Per Share | ' | ||||||||||||||||
| 10 | (Loss) Earnings Per Share | ||||||||||||||||
| The net (loss) income attributable to common stockholders and (loss) earnings per common share are presented in the table below. | |||||||||||||||||
| Three Months Ended | Six Months Ended | ||||||||||||||||
| June 30, 2013 | June 30, 2012 | June 30, 2013 | June 30, 2012 | ||||||||||||||
| $ | $ | $ | $ | ||||||||||||||
| Net loss | (5,724 | ) | (4,323 | ) | (7,677 | ) | (3,950 | ) | |||||||||
| Add: Net loss attributable to the Dropdown Predecessor | — | 5,398 | — | 9,163 | |||||||||||||
| Net (loss) income attributable to common stockholders | (5,724 | ) | 1,075 | (7,677 | ) | 5,213 | |||||||||||
| Weighted average number of common shares—basic | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 | |||||||||||||
| Weighted average number of common shares—diluted | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 | |||||||||||||
| (Loss) earnings per common share: | |||||||||||||||||
| - Basic | $ | (0.07 | ) | $ | 0.01 | $ | (0.09 | ) | $ | 0.07 | |||||||
| - Diluted | $ | (0.07 | ) | $ | 0.01 | $ | (0.09 | ) | $ | 0.07 | |||||||
Newbuilding_Agreement
| Newbuilding Agreement | 6 Months Ended | |
| Jun. 30, 2013 | ||
| Newbuilding Agreement | ' | |
| 11 | Newbuilding Agreement | |
| On April 8, 2013, the Company entered into an agreement with STX Offshore & Shipbuilding Co., Ltd (or STX) of South Korea to construct four, fuel-efficient 113,000 dead-weight tonne Long Range 2 (or LR2) product tanker newbuildings plus options to order up to an additional 12 vessels. The payment of the Company’s first shipyard installment was contingent on the Company receiving acceptable refund guarantees for the shipyard installment payments. In late-May 2013, STX commenced a voluntary financial restructuring with its lenders and as a result, STX’s refund guarantee applications were temporarily suspended. The Company has not yet received any refund guarantees as at June 30, 2013. The first installment payment required under the newbuilding agreement is equal to 10% of the contract price in respect of the initial four vessels and is due and payable within five business days after refund guarantees are received. The Company intends to finance the installment payments for the four newbuilding vessels with its existing liquidity and expects to secure long-term debt financing for the vessels prior to their scheduled deliveries in late-2015 and early-2016. According to the existing newbuilding agreement, payments required as at June 30, 2013 were $17.0 million (remainder of 2013), $8.5 million (2014), $89.0 million (2015) and $63.5 million (2016). As at June 30, 2013, the Company has not made any installment payments to STX for the four newbuilding LR2 vessels and, prior to receiving the refund guarantees, the Company has the ability to cancel the newbuilding orders at its discretion. | ||
LongTerm_Debt_Tables
| Long-Term Debt (Tables) | 6 Months Ended | ||||||||
| Jun. 30, 2013 | |||||||||
| Summary of Long-Term Debt | ' | ||||||||
| June 30, | December 31, | ||||||||
| 2013 | 2012 | ||||||||
| $ | $ | ||||||||
| Revolving Credit Facilities due through 2018 | 558,032 | 555,472 | |||||||
| Term Loans due through 2021 | 172,182 | 180,229 | |||||||
| 730,214 | 735,701 | ||||||||
| Less current portion | (25,246 | ) | (25,246 | ) | |||||
| Total | 704,968 | 710,455 | |||||||
Derivative_Instruments_Tables
| Derivative Instruments (Tables) | 6 Months Ended | ||||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||||
| Summary of Derivative Positions | ' | ||||||||||||||||||
| The following summarizes the Company’s derivative positions as at June 30, 2013: | |||||||||||||||||||
| Fair | |||||||||||||||||||
| Value / | |||||||||||||||||||
| Carrying | |||||||||||||||||||
| Amount | |||||||||||||||||||
| of Asset | |||||||||||||||||||
| (Liability) | |||||||||||||||||||
| Interest Rate Index | $ | $ | (years) | (%) (1) | |||||||||||||||
| LIBOR-Based Debt: | |||||||||||||||||||
| U.S. Dollar-denominated interest rate swap | USD LIBOR 3 month | 200,000 | (9,871 | ) | 3.3 | 2.61 | |||||||||||||
| U.S. Dollar-denominated interest rate swap | USD LIBOR 3 month | 100,000 | (16,848 | ) | 4.3 | 5.55 | |||||||||||||
| U.S. Dollar-denominated interest rate swap | USD LIBOR 3 month | 45,000 | (6 | ) | 0.1 | 1.19 | |||||||||||||
| -1 | Excludes the margin the Company pays on its variable-rate debt, which as of June 30, 2013 ranged from 0.3% to 1.0%. | ||||||||||||||||||
Financial_Instruments_Tables
| Financial Instruments (Tables) | 6 Months Ended | ||||||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||||||
| Summary of Fair Value and Carrying Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis | ' | ||||||||||||||||||||
| The following table includes the estimated fair value and carrying value of those assets and liabilities that are measured at fair value on a recurring and non-recurring basis as well as the estimated fair value of the Company’s financial instruments that are not accounted for at the fair value on a recurring basis. | |||||||||||||||||||||
| June 30, 2013 | December 31, 2012 | ||||||||||||||||||||
| Fair | Carrying | Fair | Carrying | Fair | |||||||||||||||||
| Value | Amount | Value | Amount | Value | |||||||||||||||||
| Hierarchy | Asset / | Asset / | Asset / | Asset / | |||||||||||||||||
| Level | (Liability) | (Liability) | (Liability) | (Liability) | |||||||||||||||||
| $ | $ | $ | $ | ||||||||||||||||||
| Recurring: | |||||||||||||||||||||
| Cash and cash equivalents | Level 1 | 37,708 | 37,708 | 26,341 | 26,341 | ||||||||||||||||
| Derivative instruments | |||||||||||||||||||||
| Interest rate swap agreements | Level 2 | (26,724 | ) | (26,724 | ) | (33,631 | ) | (33,631 | ) | ||||||||||||
| Non-Recurring: | |||||||||||||||||||||
| Vessels and equipment | Level 2 | — | — | 252,068 | 252,068 | ||||||||||||||||
| Vessel held for sale (note 9) | Level 2 | — | — | 9,114 | 9,114 | ||||||||||||||||
| Other: | |||||||||||||||||||||
| Investment in term loans and interest receivable | Level 3 | 122,841 | 119,929 | 119,385 | 117,784 | ||||||||||||||||
| Loan to joint venture | Note (1) | 9,830 | Note (1) | 9,830 | Note (1) | ||||||||||||||||
| Long-term debt, including current portion | Level 2 | (730,214 | ) | (654,674 | ) | (735,701 | ) | (648,724 | ) | ||||||||||||
| -1 | The Company’s loan to the joint venture, together with the Company’s equity investment in the joint venture form the aggregate carrying value of the Company’s interest in an entity accounted for by the equity method in these consolidated financial statements. The fair value of the individual components of such aggregate interest as at June 30, 2013 and December 31, 2012 was not determinable. | ||||||||||||||||||||
| Summary of Financing Receivables | ' | ||||||||||||||||||||
| The following table contains a summary of the Company’s financing receivables by type and the method by which the Company monitors the credit quality of its financing receivables on a quarterly basis. | |||||||||||||||||||||
| June 30, | December 31, | ||||||||||||||||||||
| 2013 | 2012 | ||||||||||||||||||||
| Class of Financing Receivable | Credit Quality Indicator | Grade | $ | $ | |||||||||||||||||
| Investment in term loans (see Note 2) | Collateral | Non-Performing | 122,841 | 119,385 | |||||||||||||||||
| Loan to joint venture | Other internal metrics | Performing | 9,830 | 9,830 | |||||||||||||||||
| 132,671 | 129,215 | ||||||||||||||||||||
Related_Party_Transactions_Tab
| Related Party Transactions (Tables) | 6 Months Ended | ||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||
| Summary of Related Party Transactions | ' | ||||||||||||||||
| Teekay and its wholly-owned subsidiary and the Company’s manager, Teekay Tankers Management Services Ltd. (the Manager), provide commercial, technical, strategic and administrative services to the Company. In addition, certain of the Company’s vessels participate in pooling arrangements that are managed in whole or in part by subsidiaries of Teekay (collectively the Pool Managers). The Company also has chartered out tankers to Teekay. For additional information about these arrangements, please read “Item 7 – Major Shareholders and Related Party Transactions – Related Party Transactions – Pooling Agreements” in our Annual Report on From 20-F for the year ended December 31, 2012. Amounts paid by the Company for such related party transactions for the periods indicated were as follows: | |||||||||||||||||
| Three Months | Six Months Ended | ||||||||||||||||
| Ended | |||||||||||||||||
| June 30, | June 30, | June 30, | June 30, | ||||||||||||||
| 2013 | 2012 | 2013 | 2012 | ||||||||||||||
| $ | $ | $ | $ | ||||||||||||||
| Time-charter revenues (i) | 3,671 | 3,671 | 7,302 | 7,342 | |||||||||||||
| Pool management fees and commissions (ii) | 967 | 801 | 1,997 | 1,647 | |||||||||||||
| Commercial management fees (iii) | 264 | 204 | 570 | 421 | |||||||||||||
| Vessel operating expenses—crew training | 268 | 522 | 666 | 1,102 | |||||||||||||
| Vessel operating expenses—technical management fee (iv) | 1,412 | 2,080 | 2,859 | 4,152 | |||||||||||||
| General and administrative (v) | 2,717 | 1,041 | 5,446 | 2,017 | |||||||||||||
| General and administrative—Dropdown Predecessor | — | 1,697 | — | 2,958 | |||||||||||||
| Interest Expense—Dropdown Predecessor | — | 5,335 | — | 11,658 | |||||||||||||
Loss_Earnings_Per_Share_Tables
| (Loss) Earnings Per Share (Tables) | 6 Months Ended | ||||||||||||||||
| Jun. 30, 2013 | |||||||||||||||||
| Earnings (Loss) Per Share | ' | ||||||||||||||||
| The net (loss) income attributable to common stockholders and (loss) earnings per common share are presented in the table below. | |||||||||||||||||
| Three Months Ended | Six Months Ended | ||||||||||||||||
| June 30, 2013 | June 30, 2012 | June 30, 2013 | June 30, 2012 | ||||||||||||||
| $ | $ | $ | $ | ||||||||||||||
| Net loss | (5,724 | ) | (4,323 | ) | (7,677 | ) | (3,950 | ) | |||||||||
| Add: Net loss attributable to the Dropdown Predecessor | — | 5,398 | — | 9,163 | |||||||||||||
| Net (loss) income attributable to common stockholders | (5,724 | ) | 1,075 | (7,677 | ) | 5,213 | |||||||||||
| Weighted average number of common shares—basic | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 | |||||||||||||
| Weighted average number of common shares—diluted | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 | |||||||||||||
| (Loss) earnings per common share: | |||||||||||||||||
| - Basic | $ | (0.07 | ) | $ | 0.01 | $ | (0.09 | ) | $ | 0.07 | |||||||
| - Diluted | $ | (0.07 | ) | $ | 0.01 | $ | (0.09 | ) | $ | 0.07 | |||||||
Basis_of_Presentation_Addition
| Basis of Presentation - Additional Information (Detail) (USD $) | 3 Months Ended | 6 Months Ended | ||
| In Millions, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 |
| Conventional oil tankers [Member] | ' | ' | ' | ' |
| Partnership Organization And Basis Of Presentation [Line Items] | ' | ' | ' | ' |
| Number of vessels acquired | ' | ' | ' | 13 |
| Management activities [Member] | ' | ' | ' | ' |
| Partnership Organization And Basis Of Presentation [Line Items] | ' | ' | ' | ' |
| Amount reclassified from general and administrative to vessel operating expenses | $1.40 | $2.10 | $2.90 | $4.20 |
Investment_in_Term_Loans_Addit
| Investment in Term Loans - Additional Information (Detail) (USD $) | 1 Months Ended | 3 Months Ended | 6 Months Ended | |
| Jul. 31, 2010 | Jun. 30, 2013 | Jun. 30, 2013 | Dec. 31, 2012 | |
| Vessel | Vessel | |||
| Net Investment Income [Line Items] | ' | ' | ' | ' |
| Principal amount outstanding of term loan | $115,000,000 | ' | ' | ' |
| Total amount of the term loan including costs of acquisition | 115,600,000 | ' | ' | ' |
| Interest rate on term loan | 9.00% | ' | ' | ' |
| Investment yield | 10.00% | ' | ' | ' |
| Accrued interest receivable reclassified to interest on term loans | ' | 6,600,000 | 6,600,000 | 1,600,000 |
| Interest receivable on investment in term loans | ' | ' | ' | ' |
| Repayment premium included in principal balance | ' | 3,300,000 | 3,300,000 | 2,700,000 |
| Loss provision of investment in terms loans | ' | 4,511,000 | 4,511,000 | ' |
| Accrued but unpaid interest | ' | ' | $6,600,000 | ' |
| Number of VLCC vessels to be sold | ' | 2 | 2 | ' |
Investment_in_Joint_Venture_Ad
| Investment in Joint Venture - Additional Information (Detail) (USD $) | Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2013 | Jun. 30, 2013 | Jun. 30, 2013 |
| Teekay Tankers and Wah Kwong Joint Venture [Member] | Teekay Tankers and Wah Kwong Joint Venture [Member] | Teekay Tankers and Wah Kwong Joint Venture [Member] | |||
| Installment | Installment | Joint Venture Interest Rate Derivative [Member] | |||
| Investments in and Advances to Affiliates [Line Items] | ' | ' | ' | ' | ' |
| Percentage of ownership in joint venture arrangement | ' | ' | 50.00% | 50.00% | ' |
| Equity losses recognized | ' | ' | $200,000 | $200,000 | ' |
| Secured term loan maximum amount to be drawn | ' | ' | 68,600,000 | 68,600,000 | ' |
| Quarterly installments loan | ' | ' | 32 | 32 | ' |
| Secured term loan repayments | ' | ' | ' | 1,400,000 | ' |
| Balloon payment amount | ' | ' | 22,600,000 | 22,600,000 | ' |
| Percentage Exposure to loan guarantee | 50.00% | ' | ' | ' | ' |
| Percentage of interest rate swap agreement | ' | ' | ' | ' | 1.47% |
| Investment in joint venture | 7,289,000 | 3,457,000 | ' | ' | ' |
| Amount advanced to joint venture | $9,830,000 | $9,830,000 | $9,800,000 | $9,800,000 | ' |
LongTerm_Debt_Summary_of_LongT
| Long-Term Debt - Summary of Long-Term Debt (Detail) (USD $) | Jun. 30, 2013 | Dec. 31, 2012 |
| In Thousands, unless otherwise specified | ||
| Debt Instrument [Line Items] | ' | ' |
| Long-term debt | $730,214 | $735,701 |
| Less current portion | -25,246 | -25,246 |
| Total | 704,968 | 710,455 |
| Secured Debt [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Long-term debt | 172,182 | 180,229 |
| Revolving Credit Facilities [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Long-term debt | $558,032 | $555,472 |
LongTerm_Debt_Additional_Infor
| Long-Term Debt - Additional Information (Detail) (Revolving Credit Facilities [Member], USD $) | 6 Months Ended | 12 Months Ended |
| In Millions, unless otherwise specified | Jun. 30, 2013 | Dec. 31, 2012 |
| Debt Instrument [Line Items] | ' | ' |
| Number of debt instruments | 3 | ' |
| Maximum borrowings available | 775.8 | ' |
| Undrawn amount of revolving credit facility | 217.8 | ' |
| Amount reduced under revolving credit facilities, 2013 | 47 | ' |
| Amount reduced under revolving credit facilities, 2014 | 94 | ' |
| Amount reduced under revolving credit facilities, 2015 | 120.9 | ' |
| Amount reduced under revolving credit facilities, 2016 | 89.1 | ' |
| Amount reduced under revolving credit facilities, 2017 | 395.9 | ' |
| Amount reduced under revolving credit facilities, thereafter | 28.9 | ' |
| Number of first priority mortgages granted on vessels as debt collateral | 21 | ' |
| Minimum hull coverage ratio | 105.00% | ' |
| Actual hull coverage ratio | 114.00% | ' |
| Amount of liquidity and undrawn revolving credit line | 35 | ' |
| Liquidity and undrawn revolving credit line as percentage of debt | 5.00% | ' |
| Maintain the greater of free cash liquidity for revolving credit facility | 100 | ' |
| Minimum percentage to maintaining revolving credit facility | 7.50% | ' |
| Minimum [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Percentage of margin | 0.45% | 0.45% |
| Maximum [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Percentage of margin | 0.60% | 0.60% |
LongTerm_Debt_Additional_Infor1
| Long-Term Debt - Additional Information1 (Detail) (USD $) | 6 Months Ended | 12 Months Ended |
| Jun. 30, 2013 | Dec. 31, 2012 | |
| Debt Instrument [Line Items] | ' | ' |
| Long-term debt | 730,214,000 | 735,701,000 |
| Interest at a weighted-average fixed rate | 1.20% | 1.20% |
| Amount reduced under revolving credit facilities in remaining 2013 | 12,600,000 | ' |
| Amount reduced under revolving credit facilities in 2014 | 25,200,000 | ' |
| Amount reduced under revolving credit facilities in 2015 | 58,500,000 | ' |
| Amount reduced under revolving credit facilities in 2016 | 108,100,000 | ' |
| Amount reduced under revolving credit facilities in 2017 | 415,300,000 | ' |
| Amount reduced under revolving credit facilities thereafter | 110,500,000 | ' |
| Secured Debt [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Number of debt instruments | 3 | ' |
| Long-term debt | 172,182,000 | 180,229,000 |
| Minimum hull coverage ratio | 120.00% | ' |
| Number of first priority mortgages granted on vessels as debt collateral | 6 | ' |
| Maintain the greater of free cash liquidity for revolving credit facility | 100,000,000 | ' |
| Minimum percentage to maintaining revolving credit facility | 7.50% | ' |
| Secured Debt [Member] | Minimum [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Term loan fixed interest rate | 4.06% | ' |
| Percentage of margin | 0.30% | 0.30% |
| Actual hull coverage ratio | 127.00% | ' |
| Secured Debt [Member] | Maximum [Member] | ' | ' |
| Debt Instrument [Line Items] | ' | ' |
| Term loan fixed interest rate | 4.90% | ' |
| Percentage of margin | 1.00% | 1.00% |
| Actual hull coverage ratio | 311.00% | ' |
Derivative_Instruments_Additio
| Derivative Instruments - Additional Information (Detail) (Interest rate swaps [Member], USD $) | 3 Months Ended | 6 Months Ended | ||
| In Millions, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 |
| Interest rate swaps [Member] | ' | ' | ' | ' |
| Derivative [Line Items] | ' | ' | ' | ' |
| Interest rate swaps realized losses | $2.50 | $2.40 | $4.90 | $4.80 |
| Interest rate swaps unrealized gains (losses) | 5.3 | -1.5 | 6.9 | -0.2 |
| Aggregate fair value liability | $11 | ' | $11 | ' |
Derivative_Instruments_Summary
| Derivative Instruments - Summary of Derivative Positions (Detail) (USD $) | 6 Months Ended |
| In Thousands, unless otherwise specified | Jun. 30, 2013 |
| U.S. Dollar-denominated interest rate swap 1 [Member] | ' |
| LIBOR-Based Debt: | ' |
| U.S. Dollar-denominated interest rate swap, Interest Rate Index | 'USD LIBOR 3 month |
| U.S. Dollar-denominated interest rate swap, Principal Amount | $200,000 |
| U.S. Dollar-denominated interest rate swap, Fair Value/Carrying Amount of Asset (Liability) | -9,871 |
| U.S. Dollar-denominated interest rate swap, Remaining Term (years) | '3 years 3 months 18 days |
| U.S. Dollar-denominated interest rate swap, Fixed Interest Rate | 2.61% |
| U.S. Dollar-denominated interest rate swap 2 [Member] | ' |
| LIBOR-Based Debt: | ' |
| U.S. Dollar-denominated interest rate swap, Interest Rate Index | 'USD LIBOR 3 month |
| U.S. Dollar-denominated interest rate swap, Principal Amount | 100,000 |
| U.S. Dollar-denominated interest rate swap, Fair Value/Carrying Amount of Asset (Liability) | -16,848 |
| U.S. Dollar-denominated interest rate swap, Remaining Term (years) | '4 years 3 months 18 days |
| U.S. Dollar-denominated interest rate swap, Fixed Interest Rate | 5.55% |
| U.S. Dollar-denominated interest rate swap 3 [Member] | ' |
| LIBOR-Based Debt: | ' |
| U.S. Dollar-denominated interest rate swap, Interest Rate Index | 'USD LIBOR 3 month |
| U.S. Dollar-denominated interest rate swap, Principal Amount | 45,000 |
| U.S. Dollar-denominated interest rate swap, Fair Value/Carrying Amount of Asset (Liability) | ($6) |
| U.S. Dollar-denominated interest rate swap, Remaining Term (years) | '1 month 6 days |
| U.S. Dollar-denominated interest rate swap, Fixed Interest Rate | 1.19% |
Derivative_Instruments_Summary1
| Derivative Instruments - Summary of Derivative Positions (Parenthetical) (Detail) | Jun. 30, 2013 |
| Minimum [Member] | ' |
| Derivative [Line Items] | ' |
| Margin on variable-rate debt | 0.30% |
| Maximum [Member] | ' |
| Derivative [Line Items] | ' |
| Margin on variable-rate debt | 1.00% |
Financial_Instruments_Summary_
| Financial Instruments - Summary of Fair Value and Carrying Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis (Detail) (USD $) | Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2012 | Dec. 31, 2011 |
| In Thousands, unless otherwise specified | ||||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Cash and cash equivalents | $37,708 | $26,341 | $18,554 | $18,566 |
| Loan to joint venture | 9,830 | 9,830 | ' | ' |
| Long-term debt, including current portion | -730,214 | -735,701 | ' | ' |
| Carrying Amount Asset/ (Liability) [Member] | Fair Value Measurements, Recurring [Member] | Level 1 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Cash and cash equivalents | 37,708 | 26,341 | ' | ' |
| Carrying Amount Asset/ (Liability) [Member] | Fair Value Measurements, Recurring [Member] | Level 2 [Member] | Interest rate swaps [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Interest rate swap agreements | -26,724 | -33,631 | ' | ' |
| Carrying Amount Asset/ (Liability) [Member] | Fair Value Measurements, Non-Recurring [Member] | Level 2 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Vessels and equipment | ' | 252,068 | ' | ' |
| Vessel held for sale | ' | 9,114 | ' | ' |
| Carrying Amount Asset/ (Liability) [Member] | Fair Value Measurements, Other [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Loan to joint venture | 9,830 | 9,830 | ' | ' |
| Carrying Amount Asset/ (Liability) [Member] | Fair Value Measurements, Other [Member] | Level 2 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Long-term debt, including current portion | -730,214 | -735,701 | ' | ' |
| Carrying Amount Asset/ (Liability) [Member] | Fair Value Measurements, Other [Member] | Level 3 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Investment in term loans and interest receivable | 122,841 | 119,385 | ' | ' |
| Fair Value Asset/ (Liability) [Member] | Fair Value Measurements, Recurring [Member] | Level 1 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Cash and cash equivalents | 37,708 | 26,341 | ' | ' |
| Fair Value Asset/ (Liability) [Member] | Fair Value Measurements, Recurring [Member] | Level 2 [Member] | Interest rate swaps [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Interest rate swap agreements | -26,724 | -33,631 | ' | ' |
| Fair Value Asset/ (Liability) [Member] | Fair Value Measurements, Non-Recurring [Member] | Level 2 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Vessels and equipment | ' | 252,068 | ' | ' |
| Vessel held for sale | ' | 9,114 | ' | ' |
| Fair Value Asset/ (Liability) [Member] | Fair Value Measurements, Other [Member] | Level 2 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Long-term debt, including current portion | -654,674 | -648,724 | ' | ' |
| Fair Value Asset/ (Liability) [Member] | Fair Value Measurements, Other [Member] | Level 3 [Member] | ' | ' | ' | ' |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' | ' | ' |
| Investment in term loans and interest receivable | $119,929 | $117,784 | ' | ' |
Financing_Instruments_Summary_
| Financing Instruments - Summary of Financing Receivables (Detail) (USD $) | Jun. 30, 2013 | Dec. 31, 2012 |
| In Thousands, unless otherwise specified | ||
| Financing Receivable, Recorded Investment [Line Items] | ' | ' |
| Loan to joint venture | $9,830 | $9,830 |
| Total loans and financing receivables | 132,671 | 129,215 |
| Collateral [Member] | Non-Performing [Member] | ' | ' |
| Financing Receivable, Recorded Investment [Line Items] | ' | ' |
| Investment in term loans | 122,841 | 119,385 |
| Other internal metrics [Member] | Performing [Member] | ' | ' |
| Financing Receivable, Recorded Investment [Line Items] | ' | ' |
| Loan to joint venture | $9,830 | $9,830 |
StockBased_Compensation_Additi
| Stock-Based Compensation - Additional Information (Detail) (USD $) | 6 Months Ended | 1 Months Ended | 3 Months Ended | 6 Months Ended | 1 Months Ended | ||
| Jun. 30, 2013 | Mar. 31, 2013 | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Mar. 31, 2013 | |
| Restricted Stock Units [Member] | Restricted Stock Units (RSUs) [Member] | Restricted Stock Units (RSUs) [Member] | Restricted Stock Units (RSUs) [Member] | Restricted Stock Units (RSUs) [Member] | Non-Management Director [Member] | ||
| Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] | ' | ' | ' | ' | ' | ' | ' |
| Common stock, granted | ' | ' | ' | ' | ' | ' | 142,157 |
| Common stock aggregate value, granted | ' | ' | ' | ' | ' | ' | $400,000 |
| Common stock, granted | ' | 411,629 | ' | ' | ' | ' | ' |
| Common stock, grant date fair value | ' | 1,000,000 | ' | ' | ' | ' | ' |
| Stock based compensation expense | $184,000 | ' | $100,000 | $0 | $184,000 | $0 | ' |
Related_Party_Transactions_Sum
| Related Party Transactions - Summary of Related Party Transactions (Detail) (USD $) | 3 Months Ended | 6 Months Ended | ||
| In Thousands, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 |
| Related Party Transaction [Line Items] | ' | ' | ' | ' |
| Time charter revenues | $22,710 | $32,032 | $46,888 | $67,669 |
| Vessel operating expenses | 24,832 | 23,002 | 47,886 | 46,223 |
| General and administrative | 3,362 | 2,322 | 6,923 | 3,660 |
| Interest expense | 2,604 | 6,654 | 5,115 | 14,215 |
| Affiliated Entity [Member] | ' | ' | ' | ' |
| Related Party Transaction [Line Items] | ' | ' | ' | ' |
| Time charter revenues | 3,671 | 3,671 | 7,302 | 7,342 |
| Pool management fees and commissions | 967 | 801 | 1,997 | 1,647 |
| Commercial management fees | 264 | 204 | 570 | 421 |
| General and administrative | 2,717 | 1,041 | 5,446 | 2,017 |
| Affiliated Entity [Member] | Crew training [Member] | ' | ' | ' | ' |
| Related Party Transaction [Line Items] | ' | ' | ' | ' |
| Vessel operating expenses | 268 | 522 | 666 | 1,102 |
| Affiliated Entity [Member] | Technical management fee [Member] | ' | ' | ' | ' |
| Related Party Transaction [Line Items] | ' | ' | ' | ' |
| Vessel operating expenses | 1,412 | 2,080 | 2,859 | 4,152 |
| Dropdown Predecessor [Member] | Affiliated Entity [Member] | ' | ' | ' | ' |
| Related Party Transaction [Line Items] | ' | ' | ' | ' |
| General and administrative | ' | 1,697 | ' | 2,958 |
| Interest expense | ' | $5,335 | ' | $11,658 |
Related_Party_Transactions_Sum1
| Related Party Transactions - Summary of Related Party Transactions (Parenthetical) (Detail) (Management activities [Member], USD $) | 3 Months Ended | 6 Months Ended | ||
| In Millions, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 |
| Management activities [Member] | ' | ' | ' | ' |
| Related Party Transaction [Line Items] | ' | ' | ' | ' |
| Amount reclassified from general and administrative to vessel operating expenses | $1.40 | $2.10 | $2.90 | $4.20 |
Related_Party_Transactions_Add
| Related Party Transactions - Additional Information (Detail) (USD $) | Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2012 | Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2012 | Jun. 26, 2012 | Jun. 15, 2012 | Jun. 30, 2012 | Jun. 30, 2012 | Jun. 30, 2013 | Dec. 31, 2012 |
| Share data in Millions, unless otherwise specified | Class A [Member] | Pool Managers [Member] | Pool Managers [Member] | Dropdown Predecessor [Member] | Dropdown Predecessor [Member] | Dropdown Predecessor [Member] | Conventional oil tankers [Member] | Product tankers [Member] | Asset Management [Member] | Asset Management [Member] | ||
| Vessel | Vessel | Tanker | Tanker | |||||||||
| Related Party Transaction [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
| Reimbursement of Manager's crewing and manning costs | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $4,100,000 | $4,900,000 |
| Working capital advanced to Pool Managers | 20,981,000 | 24,787,000 | ' | 19,700,000 | 16,600,000 | ' | ' | ' | ' | ' | ' | ' |
| Number of Tankers | ' | ' | ' | ' | ' | ' | 3 | 10 | 7 | 6 | ' | ' |
| Aggregate purchase price | ' | ' | ' | ' | ' | 454,200,000 | ' | ' | ' | ' | ' | ' |
| Business acquisition outstanding debt | ' | ' | ' | ' | ' | 428,100,000 | ' | ' | ' | ' | ' | ' |
| Business acquisition, number of shares issued | ' | ' | 4.5 | ' | ' | ' | ' | ' | ' | ' | ' | ' |
| Business acquisition, cash paid | ' | ' | ' | ' | ' | $1,100,000 | ' | ' | ' | ' | ' | ' |
Vessel_Sale_Additional_Informa
| Vessel Sale - Additional Information (Detail) (USD $) | 1 Months Ended | 6 Months Ended |
| In Thousands, unless otherwise specified | Jan. 31, 2013 | Jun. 30, 2013 |
| Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | ' | ' |
| Proceeds from sale of property plant and equipment | $9,119 | $9,119 |
Loss_Earnings_Per_Share_Earnin
| (Loss) Earnings Per Share - Earnings (Loss) Per Share (Detail) (USD $) | 3 Months Ended | 6 Months Ended | ||
| In Thousands, except Share data, unless otherwise specified | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 |
| (Loss) earnings per common share: | ' | ' | ' | ' |
| Net loss | ($5,724) | ($4,323) | ($7,677) | ($3,950) |
| Add: Net loss attributable to the Dropdown Predecessor | ' | 5,398 | ' | 9,163 |
| Net (loss) income attributable to common stockholders | ($5,724) | $1,075 | ($7,677) | $5,213 |
| Weighted average number of common shares-basic | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 |
| Weighted average number of common shares-diluted | 83,591,030 | 79,911,673 | 83,591,030 | 75,443,659 |
| - Basic | ($0.07) | $0.01 | ($0.09) | $0.07 |
| - Diluted | ($0.07) | $0.01 | ($0.09) | $0.07 |
Newbuilding_Agreement_Addition
| Newbuilding Agreement - Additional Information (Detail) (USD $) | 1 Months Ended | 6 Months Ended |
| In Millions, unless otherwise specified | Apr. 08, 2013 | Jun. 30, 2013 |
| Vessel | Vessel | |
| DWT | ||
| Property, Plant and Equipment [Line Items] | ' | ' |
| Weight capacity in dead-weight tonnes | 113,000 | ' |
| Number of additional vessels | 12 | ' |
| Percentage of first installment | ' | 10.00% |
| Number of new building vessels | ' | 4 |
| 2013 [Member] | ' | ' |
| Property, Plant and Equipment [Line Items] | ' | ' |
| New building agreement payments | ' | 17 |
| 2014 [Member] | ' | ' |
| Property, Plant and Equipment [Line Items] | ' | ' |
| New building agreement payments | ' | 8.5 |
| 2015 [Member] | ' | ' |
| Property, Plant and Equipment [Line Items] | ' | ' |
| New building agreement payments | ' | 89 |
| 2016 [Member] | ' | ' |
| Property, Plant and Equipment [Line Items] | ' | ' |
| New building agreement payments | ' | 63.5 |