v3.10.0.1

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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