General Information

9 Months Ended

Sep. 30, 2011

General Information [Abstract]

GENERAL INFORMATION

(1) GENERAL INFORMATION

     The condensed consolidated financial statements of GulfMark Offshore, Inc. and its subsidiaries included herein have been prepared by us without audit, pursuant to the rules and regulations of the Securities and Exchange Commission, or SEC. Unless otherwise indicated, references to “we”, “us”, “our” and the “Company” refer collectively to GulfMark Offshore, Inc. and its subsidiaries and predecessors. Certain information relating to our organization and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP, has been condensed or omitted in this Form 10-Q pursuant to such rules and regulations. However, we believe that the disclosures herein are adequate to make the information presented not misleading. The consolidated balance sheet as of December 31, 2010, has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U.S. GAAP for complete financial statements. It is recommended that these financial statements be read in conjunction with our consolidated financial statements and notes thereto included in our Form 10-K for the year ended December 31, 2010.

     In the opinion of management, all adjustments, which include reclassification and normal recurring adjustments necessary to present fairly the unaudited condensed consolidated financial statements for the periods indicated have been made. All significant intercompany accounts have been eliminated. Certain reclassifications of previously reported information may be made to conform with current year presentation.

     We provide offshore marine support and transportation services primarily to companies involved in the offshore exploration and production of oil and natural gas. Our vessels transport materials, supplies and personnel to offshore facilities, as well as move and position drilling structures. The majority of our operations are conducted in the North Sea, offshore Southeast Asia and the Americas. We also operate our vessels in other regions to meet our customers’ requirements.

Earnings Per Share

     Basic Earnings Per Share, or EPS, is computed by dividing net income (loss) by the weighted average number of shares of Class A Common Stock outstanding during the period. Diluted EPS is computed using the treasury stock method for Class A Common Stock equivalents. The reconciliation between basic and diluted earnings per share from income or loss attributable to Class A Common Stock stockholders, including allocation to participating securities, is as follows:

	Three Months Ended						Nine Months Ended
	September 30,						September 30,
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Income (loss):
Net income (loss) attributable to common stockholders	$	14,165		$	19,207		$	26,289		$	(49,981	)
Undistributed income allocated to participating securities		(100	)		(305	)		(268	)		—
Basic		14,065			18,902			26,021			(49,981	)
Undistributed income allocated to participating securities		100			305			268			—
Undistributed income reallocated to participating securities		(100	)		(303	)		(267	)		—
Diluted	$	14,065		$	18,904		$	26,022		$	(49,981	)
Shares:
Basic
Weighted-average common shares outstanding		25,869			25,599			25,793			25,512
Dilutive effect of stock options and restricted stock awards		120			138			129			—
Diluted		25,989			25,737			25,922			25,512
Income (loss) per common share:
Basic	$	0.54		$	0.74		$	1.01		$	(1.96	)
Diluted	$	0.54		$	0.73		$	1.00		$	(1.96	)