v3.8.0.1

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Accounts receivable, including affiliate balances | $ 0.8 | $ 0.6
Accumulated depreciation on vessels and equipment | 459.3 | 391.0
Accounts payable, including affiliate balances | $ 1.1 | $ 1.4
Common stock, shares authorized (in shares) | 300,000,000 | 300,000,000
Class A [Member] |  |
Common stock, shares authorized (in shares) | 200,000,000 | 200,000,000
Common stock, shares issued (in shares) | 136,100,000 | 132,800,000
Common stock, shares outstanding (in shares) | 136,100,000 | 132,800,000
Class B [Member] |  |
Common stock, shares authorized (in shares) | 100,000,000 | 100,000,000
Common stock, shares issued (in shares) | 23,200,000 | 23,200,000
Common stock, shares outstanding (in shares) | 23,200,000 | 23,200,000

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