Tidewater (TDW) 10-Q5 Nov 132014 Q2 Quarterly reportFinancial data

Company Profile

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
Document and Entity Information	Sep. 30, 2013	Oct. 25, 2013
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Trading Symbol	'TDW	'
Entity Registrant Name	'TIDEWATER INC	'
Entity Central Index Key	'0000098222	'
Current Fiscal Year End Date	'--03-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	49,584,249

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Current assets:	'	'
Cash and cash equivalents	$45,534	$40,569
Trade and other receivables, net	558,824	393,438
Marine operating supplies	53,744	62,348
Other current assets	23,653	11,735
Total current assets	681,755	508,090
Investments in, at equity, and advances to unconsolidated companies	52,254	46,047
Properties and equipment:	'	'
Vessels and related equipment	4,533,231	4,250,169
Other properties and equipment	65,791	83,779
Properties and equipment, gross	4,599,022	4,333,948
Less accumulated depreciation and amortization	1,067,673	1,144,129
Net properties and equipment	3,531,349	3,189,819
Goodwill	339,982	297,822
Other assets	149,239	126,277
Total assets	4,754,579	4,168,055
LIABILITIES AND STOCKHOLDERS' EQUITY	'	'
Accrued property and liability losses	4,099	4,133
Current liabilities:	'	'
Accounts payable	89,689	63,602
Accrued expenses	168,185	159,086
Accrued property and liability losses	4,099	4,133
Other current liabilities	39,334	39,808
Total current liabilities	301,307	266,629
Long-term debt	1,445,628	1,000,000
Deferred income taxes	188,771	189,763
Other liabilities and deferred credits	174,370	139,074
Commitments and Contingencies (Note 8)	'	'
Stockholders' equity:	'	'
Common stock of $0.10 par value, 125,000,000 shares authorized, issued 49,577,276 shares at September 30, 2013 and 49,485,832 shares at March 31, 2013	4,958	4,949
Additional paid-in capital	133,386	119,975
Retained earnings	2,513,193	2,453,973
Accumulated other comprehensive loss	-16,970	-17,141
Total stockholders' equity	2,634,567	2,561,756
Total liabilities and stockholders' equity	4,754,579	4,168,055
Noncurrent Liabilities	'	'
LIABILITIES AND STOCKHOLDERS' EQUITY	'	'
Accrued property and liability losses	9,936	10,833
Current liabilities:	'	'
Accrued property and liability losses	$9,936	$10,833

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Mar. 31, 2013
Common stock, par value	$0.10	$0.10
Common stock, shares authorized	125,000,000	125,000,000
Common stock, issued	49,577,276	49,485,832

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Earnings (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:	'	'	'	'
Vessel revenues	$363,668	$309,822	$695,298	$599,916
Other operating revenues	4,269	2,096	6,724	6,450
Total revenues	367,937	311,918	702,022	606,366
Costs and expenses:	'	'	'	'
Vessel operating costs	195,316	172,652	391,477	333,988
Costs of other operating revenues	4,040	1,585	6,060	5,108
General and administrative	46,038	41,867	96,518	82,531
Vessel operating leases	3,971	4,403	8,002	8,895
Depreciation and amortization	42,056	36,047	82,164	71,831
Gain on asset dispositions, net	-49	-1,833	-2,189	-2,671
Total costs and expenses	291,372	254,721	582,032	499,682
Operating income	76,565	57,197	119,990	106,684
Other income (expenses):	'	'	'	'
Foreign exchange gain (loss)	3,017	529	2,928	-1,222
Equity in net earnings of unconsolidated companies	3,781	3,357	8,201	5,720
Interest income and other, net	538	1,128	1,278	1,847
Loss on early extinguishment of debt	-4,144	'	-4,144	'
Interest and other debt costs	-9,918	-7,148	-18,831	-14,735
Total other income (expenses)	-6,726	-2,134	-10,568	-8,390
Earnings before income taxes	69,839	55,063	109,422	98,294
Income tax expense	15,667	13,707	25,167	24,082
Net earnings	$54,172	$41,356	$84,255	$74,212
Basic earnings per common share	$1.10	$0.84	$1.71	$1.49
Diluted earnings per common share	$1.09	$0.83	$1.70	$1.48
Weighted average common shares outstanding	49,274,816	49,392,973	49,253,409	49,792,212
Dilutive effect of stock options and restricted stock	448,303	232,097	395,983	214,291
Adjusted weighted average common shares	49,723,119	49,625,070	49,649,392	50,006,503
Cash dividends declared per common share	$0.25	$0.25	$0.50	$0.50

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net earnings	$54,172	$41,356	$84,255	$74,212
Other comprehensive income/(loss):	'	'	'	'
Unrealized gains/(losses) on available-for-sale securities net of tax of $(93), $225, $(33) and $(110)	-173	419	-62	-205
Amortization of loss on derivative contract net of tax of $62, $63, $125 and $125	116	117	233	233
Total comprehensive income	$54,115	$41,892	$84,426	$74,240

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Unrealized gains/(losses) on available-for-sale securities, tax	($93)	$225	($33)	($110)
Amortization of loss on derivative contract, tax	$62	$63	$125	$125

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Cash Flows (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Operating activities:	'	'
Net earnings	$84,255	$74,212
Adjustments to reconcile net earnings to net cash provided by operating activities:	'	'
Depreciation and amortization	82,164	71,831
Benefit for deferred income taxes	-10,215	-4,372
Gain on asset dispositions, net	-2,189	-2,671
Equity in earnings of unconsolidated companies, less dividends	-6,167	-4,031
Compensation expense - stock-based	10,999	10,320
Excess tax benefit on stock options exercised	-341	-95
Changes in assets and liabilities, net:	'	'
Trade and other receivables	-165,573	-20,707
Marine operating supplies	9,363	-2,281
Other current assets	-10,666	-5,565
Accounts payable	11,461	16,195
Accrued expenses	8,631	6,176
Accrued property and liability losses	39	-241
Other current liabilities	276	1,134
Other liabilities and deferred credits	-531	3,508
Other, net	-1,678	2,846
Net cash provided by operating activities	9,828	146,259
Cash flows from investing activities:	'	'
Proceeds from sales of assets	7,646	9,977
Proceeds from sale/leaseback of assets	65,550	'
Additions to properties and equipment	-220,309	-189,826
Payments for acquisition, net of cash acquired	-127,737	'
Other	-687	-1,338
Net cash used in investing activities	-275,537	-181,187
Cash flows from financing activities:	'	'
Debt issuance costs	-3,845	'
Principal payment on long-term debt	-691,615	-60,000
Debt borrowings	986,262	'
Proceeds from exercise of stock options	4,421	938
Cash dividends	-24,890	-25,058
Excess tax benefit on stock options exercised	341	95
Stock repurchases	'	-65,028
Net cash provided by (used in) financing activities	270,674	-149,053
Net change in cash and cash equivalents	4,965	-183,981
Cash and cash equivalents at beginning of period	40,569	320,710
Cash and cash equivalents at end of period	45,534	136,729
Cash paid during the period for:	'	'
Interest	23,338	19,259
Income taxes	32,144	27,075
Supplemental disclosure of non-cash investing activities:	'	'
Additions to properties and equipment	4,157	6,724
Increase in receivables due to sale of shipyard	$6,500	'

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Stockholders' Equity (USD $)	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive loss
In Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive loss
Beginning balance at Mar. 31, 2012	$2,526,357	$5,125	$102,726	$2,437,836	($19,330)
Total comprehensive income	74,240	'	'	74,212	28
Stock option activity	2,151	3	2,148	'	'
Cash dividends declared	-25,169	'	'	-25,169	'
Retirement of common stock	-65,028	-140	'	-64,888	'
Amortization/cancellation of restricted stock units	3,867	'	3,867	'	'
Amortization/cancellation of restricted stock	3,859	-6	3,865	'	'
Ending Balance at Sep. 30, 2012	2,520,277	4,982	112,606	2,421,991	-19,302
Beginning balance at Mar. 31, 2013	2,561,756	4,949	119,975	2,453,973	-17,141
Total comprehensive income	84,426	'	'	84,255	171
Stock option activity	4,775	12	4,763	'	'
Cash dividends declared	-25,035	'	'	-25,035	'
Amortization/cancellation of restricted stock units	6,220	'	6,220	'	'
Amortization/cancellation of restricted stock	2,425	-3	2,428	'	'
Ending Balance at Sep. 30, 2013	$2,634,567	$4,958	$133,386	$2,513,193	($16,970)

Interim_Financial_Statements

Interim Financial Statements	6 Months Ended
	Sep. 30, 2013
Interim Financial Statements	'
	-1	INTERIM FINANCIAL STATEMENTS
	The unaudited condensed consolidated financial statements for the interim periods presented herein have been prepared in conformity with United States generally accepted accounting principles and, in the opinion of management, include all adjustments (consisting only of normal recurring adjustments) necessary for a fair presentation of the unaudited condensed consolidated financial statements at the dates and for the periods indicated as required by Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (SEC). Results of operations for interim periods are not necessarily indicative of results of operations for the respective full years. These unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto in the company’s Annual Report on Form 10-K for the year ended March 31, 2013, filed with the SEC on May 21, 2013.
	The unaudited condensed consolidated financial statements include the accounts of Tidewater Inc. and its subsidiaries. Intercompany balances and transactions are eliminated in consolidation. The company uses the equity method to account for equity investments over which the company exercises significant influence but does not exercise control and is not the primary beneficiary. Unless otherwise specified, all per share information included in this document is on a diluted earnings per share basis.
	The company made certain reclassifications to prior period amounts to conform to the current year presentation. These reclassifications did not have a material effect on the condensed consolidated statements of earnings, balance sheets or cash flows.

Acquisition

Acquisition	6 Months Ended
Acquisition	Sep. 30, 2013
Acquisition	'
	-2	ACQUISITION
	Troms Offshore Supply AS
	On June 4, 2013, the company, through a subsidiary, acquired Troms Offshore Supply AS, a Norwegian company (Troms Offshore). At the time of the acquisition, Troms Offshore owned four deepwater PSVs, and had two additional deepwater PSVs under construction, one of which was delivered shortly after the acquisition. The purchase price (not including transaction costs) included a $150.0 million cash payment to the shareholders of Troms Offshore and the assumption of approximately $261.3 million of combined Troms Offshore obligations, comprised of net interest-bearing debt and the remaining installment payments due on vessels under construction. The company has performed a fair value analysis and the purchase price was allocated to the acquired assets and liabilities based on their fair values resulting in $42.2 million of goodwill, all of which was allocated to our Sub-Saharan Africa/Europe segment. The allocation is preliminary and based on estimates and assumptions that are subject to change within the purchase price allocation period (generally one year from the acquisition date).
	The following table summarizes the allocation of the purchase price for the acquisition of Troms Offshore:


	(In thousands)
	Cash		$	22,263
	Trade receivables and other current assets			9,816
	Vessels			245,605
	Goodwill			42,160
	Payable and other liabilities			(13,020	)
	Notes payable			(156,824	)

	Total purchase price		$	150,000

	The effect of the acquisition on pro forma results of operations and the condensed consolidated statement of operations for the six months ended September 30, 2013 are immaterial and therefore not presented.

Stockholders_Equity

Stockholders' Equity	6 Months Ended
Stockholders' Equity	Sep. 30, 2013
Stockholders' Equity	'
	-3	STOCKHOLDERS’ EQUITY
	Common Stock Repurchase Program
	On May 15, 2013, the company’s Board of Directors authorized the company to spend up to $200 million to repurchase shares of its common stock in open-market or privately-negotiated transactions. The effective period for this authorization is July 1, 2013 through June 30, 2014. The company uses its available cash and, when considered advantageous, borrowings under its revolving credit facility or other borrowings, to fund any share repurchases. The company evaluates share repurchase opportunities relative to other investment opportunities and in the context of current conditions in the credit and capital markets.
	On May 17, 2012, the company’s Board of Directors authorized the company to spend up to $200.0 million to repurchase shares of its common stock in open-market or privately-negotiated transactions. The effective period for this authorization was July 1, 2012 through June 30, 2013.
	The aggregate dollar outlay for common stock repurchased, along with number of shares repurchased, and average price paid per share, for the quarters and six-month periods ended September 30 is as follows:


			Quarter Ended							Six Months Ended
			September 30,							September 30,
	(In thousands, except share and per share data)		2013			2012				2013				2012
	Aggregate dollar outlay for common stock repurchased		$	---			---				---				65,028
	Shares of common stock repurchased			---			---				---				1,400,500
	Average price paid per common share		$	---			---				---				46.43

	Dividends
	The declaration of dividends is at the discretion of the company’s Board of Directors. The Board of Directors declared the following dividends for the quarters and six-month periods ended September 30:


			Quarter Ended							Six Months Ended
			September 30,							September 30,
	(In thousands, except dividend per share)		2013			2012				2013				2012
	Dividends declared		$	12,536			12,544				25,035				25,169
	Dividend per share			0.25			0.25				0.5				0.5


	Accumulated Other Comprehensive Loss
	The changes in accumulated other comprehensive income by component, net of tax for the quarters and six month periods ended September 30, 2013 and 2012 are as follows:


			For the quarter ended September 30, 2013																	For the six months ended September 30, 2013
	(in thousands)		Balance			Gains/				Reclasses				Net			Remaining			Balance			Gains/			Reclasses		Net			Remaining
			at			(losses)				from OCI				period			balance			at			(losses)			from OCI		period			balance
			6/30/13			recognized				to net				OCI			9/30/13			3/31/13			recognized			to net		OCI			9/30/13
						in OCI				income													in OCI			income
	Available for sale securities			(10	)		(237	)			64				(173	)		(183	)		(121	)		(206	)		144		(62	)		(183	)
	Currency translation adjustment			(9,811	)		---				---				---			(9,811	)		(9,811	)		---			---		---			(9,811	)
	Pension/Post-retirement benefits			(4,353	)		---				---				---			(4,353	)		(4,353	)		---			---		---			(4,353	)
	Interest rate swaps			(2,739	)		---				116				116			(2,623	)		(2,856	)		---			233		233			(2,623	)

	Total			(16,913	)		(237	)			180				(57	)		(16,970	)		(17,141	)		(206	)		377		171			(16,970	)


			For the quarter ended September 30, 2012																	For the six months ended September 30, 2012
	(in thousands)		Balance			Gains/				Reclasses				Net			Remaining			Balance			Gains/			Reclasses		Net			Remaining
			at			(losses)				from OCI				period			balance			at			(losses)			from OCI		period			balance
			6/30/12			recognized				to net				OCI			9/30/12			3/31/12			recognized			to net		OCI			9/30/12
						in OCI				income													in OCI			income
	Available for sale securities			(373	)		410				9				419			46			251			(351	)		146		(205	)		46
	Currency translation adjustment			(9,811	)		---				---				---			(9,811	)		(9,811	)		---			---		---			(9,811	)
	Pension/Post-retirement benefits			(6,448	)		---				---				---			(6,448	)		(6,448	)		---			---		---			(6,448	)
	Interest rate swaps			(3,206	)		---				117				117			(3,089	)		(3,322	)		---			233		233			(3,089	)

	Total			(19,838	)		410				126				536			(19,302	)		(19,330	)		(351	)		379		28			(19,302	)

	The following table summarizes the reclassifications from accumulated other comprehensive loss to the condensed consolidated statement of income for the quarters and six month periods ended September 30, 2013 and 2012:


			Quarter Ended									Six Months Ended								Affected line item in the condensed
			September 30,									September 30,								consolidated statements of income
	(In thousands)		2013					2012				2013					2012
	Realized gains on available for-sale securities		$	99					15				222					225		Interest income and other, net
	Amortization of interest rate swap			178					180				358					358		Interest and other debt costs

Total pre-tax amounts			277					195				580					583
Tax effect			97					68				203					204

Total gains for the period, net of tax		$	180					127				377					379

Income_Taxes

Income Taxes	6 Months Ended
Income Taxes	Sep. 30, 2013
Income Taxes	'
	-4	INCOME TAXES
	Income tax expense for interim periods is based on estimates of the effective tax rate for the entire fiscal year. The effective tax rate applicable to pre-tax earnings, for the quarters and the six-month periods ended September 30, is as follows:


			Quarter Ended						Six Months Ended
			September 30,						September 30,
			2013			2012			2013			2012
	Effective tax rate applicable to pre-tax earnings			22.4	%		24.9	%		23	%		24.5	%

	The effective tax rates for the six months ended September 30, 2013 and 2012 are lower than the U.S. statutory income tax rate of 35% primarily because the company has not recognized a U.S. deferred tax liability associated with temporary differences related to investments in foreign subsidiaries that are essentially permanent in duration.

	The company’s balance sheet at September 30, 2013 reflects the following in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 740, Income Taxes:


	(In thousands)		September 30,
	(In thousands)		2013
	Tax liabilities for uncertain tax positions		$	16,304
	Income tax payable			32,787

	The tax liabilities for uncertain tax positions are attributable to a permanent establishment issue related to a foreign joint venture. Penalties and interest related to income tax liabilities are included in income tax expense. Income tax payable is included in other current liabilities.
	Unrecognized tax benefits, which would lower the effective tax rate if realized at September 30, 2013, are as follows:


	(In thousands)		September 30,
	(In thousands)		2013
	Unrecognized tax benefit related to state tax issues		$	8,202
	Interest receivable on unrecognized tax benefit related to state tax issues			20

	With limited exceptions, the company is no longer subject to tax audits by U.S. federal, state, local or foreign taxing authorities for years prior to 2006. The company has ongoing examinations by various U.S. federal, state and foreign tax authorities and does not believe that the results of these examinations will have a material adverse effect on the company’s financial position, results of operations, or cash flows.

Employee_Benefit_Plans

Employee Benefit Plans	6 Months Ended
Employee Benefit Plans	Sep. 30, 2013
Employee Benefit Plans	'
	-5	EMPLOYEE BENEFIT PLANS
	U.S. Defined Benefit Pension Plan
	The company has a defined benefit pension plan (pension plan) that covers certain U.S. citizen employees and other employees who are permanent residents of the United States. In December 2009, the Board of Directors amended the pension plan to discontinue the accrual of benefits once the plan was frozen on December 31, 2010. This change did not affect benefits earned by participants prior to January 1, 2011. The company did not contribute to the defined benefit pension plan during the quarters and six months ended September 30, 2013 and 2012, and does not expect to contribute to the plan during the remaining quarters of fiscal 2014.
	Supplemental Executive Retirement Plan
	The company also offers a non-contributory, defined benefit supplemental executive retirement plan (supplemental plan) that provides pension benefits to certain employees in excess of those allowed under the company’s tax-qualified pension plan. A Rabbi Trust has been established for the benefit of participants in the supplemental plan. The Rabbi Trust assets, which are invested in a variety of marketable securities (but not Tidewater stock), are recorded at fair value with unrealized gains or losses included in other comprehensive income. Effective March 4, 2010, the supplemental plan was closed to new participation. The supplemental plan is a non-qualified plan and, as such, the company is not required to make contributions to the supplemental plan. The company did not contribute to the supplemental plan during the quarters and six- month periods ended September 30, 2013 and 2012 and does not expect to contribute to the plan during the remaining quarters of fiscal 2014.
	Investments held in a Rabbi Trust for the benefit of participants in the supplemental plan are included in other assets at fair value. The following table summarizes the carrying value of the trust assets, including unrealized gains or losses at September 30, 2013 and March 31, 2013:


	(In thousands)		September 30,			March 31,
	(In thousands)		2013			2013
	Investments held in Rabbi Trust		$	10,182			10,486
	Unrealized gains (losses) in fair value of trust assets			(183	)		(121	)
	Unrealized gains (losses) in fair value of trust assets are net of income tax expense of			(98	)		(65	)
	Obligations under the supplemental plan			22,260			21,431


	The unrealized gains or losses in the fair value of the trust assets, net of income tax expense, are included in accumulated other comprehensive income (other stockholders’ equity). To the extent that trust assets are liquidated to fund benefit payments, gains or losses, if any, will be recognized at that time. The company’s obligations under the supplemental plan are included in ‘accrued expenses’ and ‘other liabilities and deferred credits’ on the consolidated balance sheet.
	Postretirement Benefit Plan
	Qualified retired employees currently are covered by a program which provides limited health care and life insurance benefits. Costs of the program are based on actuarially determined amounts and are accrued over the period from the date of hire to the full eligibility date of employees who are expected to qualify for these benefits. This plan is funded through payments as benefits are required.
	Net Periodic Benefit Costs
	The net periodic benefit cost for the company’s U.S. defined benefit pension plan and the supplemental plan (referred to collectively as “Pension Benefits”) and the postretirement health care and life insurance plan (referred to collectively as “Other Benefits”) is comprised of the following components:


			Quarter Ended						Six Months Ended
			September 30,						September 30,
	(In thousands)		2013			2012			2013			2012
	Pension Benefits:
	Service cost		$	198			273			396			546
	Interest cost			895			1,072			1,790			2,144
	Expected return on plan assets			(718	)		(687	)		(1,436	)		(1,374	)
	Amortization of prior service cost			12			12			24			24
	Recognized actuarial loss			276			448			552			896

	Net periodic benefit cost		$	663			1,118			1,326			2,236

	Other Benefits:
	Service cost		$	101			119			202			238
	Interest cost			262			309			524			618
	Amortization of prior service cost			(508	)		(508	)		(1,016	)		(1,016	)
	Recognized actuarial (gain) loss			(99	)		---			(198	)		---

	Net periodic benefit cost		$	(244	)		(80	)		(488	)		(160	)

Indebtedness

Indebtedness	6 Months Ended
Indebtedness	Sep. 30, 2013
Indebtedness	'
	-6	INDEBTEDNESS
	Revolving Credit and Term Loan Agreement
	In June 2013, the company amended and extended its existing credit facility. The amended credit agreement matures in June 2018 (the “Maturity Date”) and provides for a $900 million, five-year credit facility (“credit facility”) consisting of a (i) $600 million revolving credit facility (the “revolver”) and a (ii) $300 million term loan facility (“term loan”).
	Borrowings under the credit facility are unsecured and bear interest at the company’s option at (i) the greater of prime or the federal funds rate plus 0.25 to 1.0%, or (ii) Eurodollar rates plus margins ranging from 1.25 to 2.0%, based on the company’s consolidated funded debt to capitalization ratio. Commitment fees on the unused portion of the facilities range from 0.15 to 0.30% based on the company’s funded debt to total capitalization ratio. The credit facility requires that the company maintain a ratio of consolidated debt to consolidated total capitalization that does not exceed 55%, and maintain a consolidated interest coverage ratio (essentially consolidated earnings before interest, taxes, depreciation and amortization, or EBITDA, for the four prior fiscal quarters to consolidated interest charges, including capitalized interest, for such period) of not less than 3.0 to 1.0. All other terms, including the financial and negative covenants, are customary for facilities of its type and consistent with the prior agreement in all material respects.
	The company had $300 million in term loan borrowings, and $180 million in revolver borrowings, outstanding at September 30, 2013 (whose fair value approximates the carrying value because the borrowings bear interest at variable rates), and has $420.0 million of availability for future financing needs at September 30, 2013. The company had $125 million of term loan borrowings and $110.0 million of revolver borrowings outstanding under the previous credit facility at March 31, 2013. These estimated fair values are based on Level 2 inputs.

	Senior Debt Notes
	The determination of fair value includes an estimated credit spread between our long term debt and treasuries with similar matching expirations. The credit spread is determined based on comparable publicly traded companies in the oilfield service segment with similar credit ratings. These estimated fair values are based on Level 2 inputs.
	September 2013 Senior Notes
	On September 30, 2013, the company executed a note purchase agreement for $500 million and issued $300 million of senior unsecured notes to a group of institutional investors. In accordance with the note purchase agreement, the company intends to issue the remaining $200 million of senior unsecured notes on November 15, 2013. A summary of these notes outstanding at September 30, 2013, is as follows:


	(In thousands, except weighted average data)		September 30,
	(In thousands, except weighted average data)		2013
	Aggregate debt outstanding		$	300,000
	Weighted average remaining life in years			9.3
	Weighted average coupon rate on notes outstanding			4.73	%
	Fair value of debt outstanding			307,601

	The multiple series of notes totaling $300 million were originally issued with maturities ranging from approximately seven to 12 years. The multiple series of notes totaling $200 million to be issued November 15, 2013 will have original maturities of ten and 12 years, a weighted average life of 10.8 years and a weighted average coupon rate of 5.06%. The notes may be retired before their respective scheduled maturity dates subject only to a customary make-whole provision. The terms of the notes require that the company maintain a ratio of consolidated debt to consolidated total capitalization that does not exceed 55% and maintain a ratio of consolidated EBITDA to consolidated interest charges, including capitalized interest, of not less than 3.0 to 1.0.
	August 2011 Senior Notes
	On August 15, 2011, the company issued $165 million of senior unsecured notes to a group of institutional investors. A summary of these notes outstanding at September 30, 2013 and March 31, 2013, is as follows:


	(In thousands, except weighted average data)		September 30,				March 31,
	(In thousands, except weighted average data)		2013				2013
	Aggregate debt outstanding		$	165,000				165,000
	Weighted average remaining life in years			7.1				7.6
	Weighted average coupon rate on notes outstanding			4.42	%			4.42	%
	Fair value of debt outstanding			169,686				179,802

	The multiple series of notes were originally issued with maturities ranging from approximately eight to 10 years. The notes may be retired before their respective scheduled maturity dates subject only to a customary make-whole provision. The terms of the notes require that the company maintain a ratio of consolidated debt to consolidated total capitalization that does not exceed 55%.

	September 2010 Senior Notes
	In fiscal 2011, the company completed the sale of $425 million of senior unsecured notes. A summary of the aggregate amount of these notes outstanding at September 30, 2013 and March 31, 2013, is as follows:


	(In thousands, except weighted average data)		September 30,				March 31,
	(In thousands, except weighted average data)		2013				2013
	Aggregate debt outstanding		$	425,000				425,000
	Weighted average remaining life in years			6.1				6.6
	Weighted average coupon rate on notes outstanding			4.25	%			4.25	%
	Fair value of debt outstanding			436,530				458,520

	The multiple series of these notes were originally issued with maturities ranging from five to 12 years. The notes may be retired before their respective scheduled maturity dates subject only to a customary make-whole provision. The terms of the notes require that the company maintain a ratio of consolidated debt to consolidated total capitalization that does not exceed 55%.
	Included in accumulated other comprehensive income at September 30, 2013 and March 31, 2013, is an after-tax loss of $2.6 million ($4.0 million pre-tax), and $2.9 million ($4.4 million pre-tax), respectively, relating to the purchase of interest rate hedges, which are cash flow hedges, in July 2010 in connection with the September 2010 senior notes offering. The interest rate hedges settled in August 2010 concurrent with the pricing of the senior unsecured notes. The hedges met the effectiveness criteria and their acquisition costs are amortized to interest expense over the term of the individual notes matching the term of the hedges.
	July 2003 Senior Notes
	In July 2003, the company completed the sale of $300 million of senior unsecured notes. A summary of the aggregate amount of remaining senior unsecured notes outstanding at September 30, 2013 and March 31, 2013, is as follows:


	(In thousands, except weighted average data)		September 30,				March 31,
	(In thousands, except weighted average data)		2013				2013
	Aggregate debt outstanding		$	35,000				175,000
	Weighted average remaining life in years			1.8				0.7
	Weighted average coupon rate on notes outstanding			4.61	%			4.47	%
	Fair value of debt outstanding			36,454				178,227

	The multiple series of notes were originally issued with maturities ranging from seven to 12 years. These notes can be retired in whole or in part prior to maturity for a redemption price equal to the principal amount of the notes redeemed plus a customary make-whole premium. The terms of the notes require that the company maintain a ratio of consolidated debt to consolidated total capitalization that does not exceed 55%.
	Troms Offshore Debt
	During the second quarter of fiscal 2014, the company repaid prior to maturity 500 million Norwegian Kroner (NOK) denominated (approximately $82.1 million) public bonds (plus accrued interest) that had been issued by Troms Offshore in April 2013. The repayment of these bonds, at an average price of approximately 105.0% of par value, resulted in the recognition of a loss on early extinguishment of debt of approximately 26.0 million NOK (or $4.1 million). The bonds, which were due to mature in April 2016, bore interest based on the three month Norwegian Interbank Offered Rate (“NIBOR”) plus 5.40%.
	In May 2012, Troms Offshore entered into a 204.4 million NOK denominated borrowing agreement which matures in May 2024. The loan requires semi-annual principal payments of 8.5 million NOK, bears interest at a fixed rate of 6.38% and is secured by certain guarantees and various types of collateral, including a vessel. As of September 30, 2013, 187.4 million NOK (approximately $30.8 million) is outstanding under this agreement.

	In May 2012, Troms Offshore entered into a 35.0 million NOK denominated borrowing agreement with a shipyard which matures in May 2015. In June 2013, Troms Offshore entered into a 25.0 million NOK denominated borrowing agreement with a Norwegian bank, which matures in June 2019. These borrowings bear interest based on three month NIBOR plus a credit spread of 2.0% to 3.5%. As of September 30, 2013, 60.0 million NOK (approximately $9.9 million) is outstanding under these agreements.
Troms Offshore had 60.0 million NOK, or approximately $9.9 million, outstanding in floating rate debt at September 30, 2013 (whose fair value approximates the carrying value because the borrowings bear interest at variable NIBOR rates plus a margin). Troms Offshore also had 187.4 million NOK, or $30.8 million, of outstanding fixed rate debt at September 30, 2013 which has an estimated fair value of 196.6 million NOK, or $32.3 million. These estimated fair values are based on Level 2 inputs.
In June 2013, Troms Offshore repaid a 188.9 million NOK loan (approximately $32.5 million), plus accrued interest that was secured with various guarantees and collateral, including a vessel.
Current Maturities of Long Term Debt
Principal repayments of approximately $5.3 million due during the twelve months ending September 30, 2014 are classified as long term debt in the accompanying balance sheet at September 30, 2013 because the company has the ability and intent to fund the repayments with borrowings under the credit facility which matures in June 2018.
Debt Costs
The company capitalizes a portion of its interest costs incurred on borrowed funds used to construct vessels. Interest and debt costs incurred, net of interest capitalized, for the quarters and the six-month periods ended September 30, are as follows:


		Quarter Ended								Six Months Ended
		September 30,								September 30,
(In thousands)		2013				2012				2013		2012
Interest and debt costs incurred, net of interest capitalized		$	9,918				7,148				18,831		14,735
Interest costs capitalized			2,636				2,913				5,598		5,736

Total interest and debt costs		$	12,554				10,061				24,429		20,471

Earnings_Per_Share

Earnings Per Share	6 Months Ended
Earnings Per Share	Sep. 30, 2013
Earnings Per Share	'
	-7	EARNINGS PER SHARE
	The components of basic and diluted earnings per share for the quarters and the six-month periods ended September 30, are as follows:


			Quarter Ended				Six Months Ended
			September 30,				September 30,
	(In thousands, except share and per share data)		2013		2012		2013		2012
	Net Income available to common shareholders (A)		$	54,172		41,356		84,255		74,212
	Weighted average outstanding shares of common stock, basic (B)			49,274,816		49,392,973		49,253,409		49,792,212
	Dilutive effect of options and restricted stock awards and units			448,303		232,097		395,983		214,291

	Weighted average common stock and equivalents (C)			49,723,119		49,625,070		49,649,392		50,006,503

	Earnings per share, basic (A/B)		$	1.1		0.84		1.71		1.49
	Earnings per share, diluted (A/C)		$	1.09		0.83		1.7		1.48

	Additional information:
	Antidilutive incremental options and restricted stock awards and units			2,854		54,694		2,854		51,864

Commitments_and_Contingencies

Commitments and Contingencies

6 Months Ended

Sep. 30, 2013

Commitments and Contingencies

-8

COMMITMENTS AND CONTINGENCIES

Vessel and Other Commitments

The table below summarizes the company’s various vessel commitments to acquire and construct new vessels, by vessel type, and remotely operated vehicles (ROVs) as of September 30, 2013:

(In thousands, except vessel count)

Number

Total

Invested

Remaining

Cost

Through

Balance

Vessels/ROVs

9/30/13

Vessels under construction:

Deepwater platform supply vessels

739,794

233,436

506,358

Towing supply/supply vessels

113,395

46,506

66,889

Other

33,917

28,455

5,462

Total vessels under construction

887,106

308,397

578,709

Vessels to be purchased:

Deepwater platform supply vessels

46,845

---

46,845

Total vessel commitments

933,951

308,397

625,554

Total ROV commitments

26,167

7,850

18,317

Total commitments

960,118

316,247

643,871

The total cost of the various vessel new-build commitments includes contract costs and other incidental costs. The company has vessels under construction at a number of different shipyards around the world. The deepwater platform supply vessels (PSV) under construction range between 3,000 and 6,360 deadweight tons (DWT) of cargo capacity while the towing-supply/supply vessels under construction have 7,100 brake horsepower (BHP). Scheduled delivery for the new-build vessels began in October 2013, with delivery of the final new-build vessel expected in February 2016. The company also has new-build commitments for five ROVs at September 30, 2013 with delivery dates between October and December of 2013.

With its commitment to modernizing its fleet through its vessel construction and acquisition program over the past decade, the company is replacing its older fleet of vessels with fewer, larger and more efficient vessels, while also enhancing the size and capabilities of the company’s fleet. These efforts are expected to continue, with the company anticipating that it will use some portion of its future operating cash flows and existing borrowing capacity as well as possible new borrowings or lease arrangements in order to fund current and future commitments in connection with the fleet renewal and modernization program. The company continues to evaluate its fleet renewal program, whether through new construction or acquisitions, relative to other investment opportunities and uses of cash, including the current share repurchase authorization, and in the context of current conditions in the credit and capital markets.

Currently the company is experiencing substantial delay with one fast supply boat under construction in Brazil that was originally scheduled to be delivered in September 2009. On April 5, 2011, pursuant to the vessel construction contract, the company sent the subject shipyard a letter initiating arbitration in order to resolve disputes of such matters as the shipyard’s failure to achieve payment milestones, its failure to follow the construction schedule, and its failure to timely deliver the vessel. The company has suspended construction on the vessel and both parties continue to pursue that arbitration. The company has third party credit support in the form of insurance coverage for 90% of the progress payments made on this vessel, or all but approximately $2.4 million of the carrying value of the accumulated costs through September 30, 2013. The company had committed and invested $8.0 million as of September 30, 2013.

In October 2013, the company took delivery of the first of two deepwater PSVs constructed in a U.S. Shipyard. In connection with that delivery, the company and the shipyard agreed to hold $7.8 million in escrow with a financial institution pending resolution of disputes over whether all or a portion of those funds are due to the shipyard as the shipyard has claimed. Monies held in escrow are included in Total Cost and Remaining Balance 9/30/2013 that is summarized above under Vessel and Other Commitments. Some of the disputes may be resolved by high level management meetings between the parties or through a relatively expeditious technical arbitration proceeding involving a third party technical expert. The balance of the claims will need to be resolved through litigation in New York state court. These formal dispute resolution efforts are currently at an early stage.

The company generally requires shipyards to provide third party credit support in the event that vessels are not completed and delivered timely and in accordance with the terms of the shipbuilding contracts. That third party credit support typically guarantees the return of amounts paid by the company and generally takes the form of refundment guarantees or standby letters of credit issued by major financial institutions located in the country of the shipyard. While the company seeks to minimize its shipyard credit risk by requiring these instruments, the ultimate return of amounts paid by the company in the event of shipyard default is still subject to the creditworthiness of the shipyard and the provider of the credit support, as well as the company’s ability to successfully pursue legal action to compel payment of these instruments. When third party credit support is not available or cost effective, the company endeavors to limit its credit risk by minimizing pre-delivery payments and through other contract terms with the shipyard.

Completion of Internal Investigation and Settlements with United States and Nigerian Agencies

The company has previously reported that special counsel engaged by the company’s Audit Committee had completed an internal investigation into certain Foreign Corrupt Practices Act (FCPA) matters and reported its findings to the Audit Committee. The substantive areas of the internal investigation have been reported publicly by the company in prior filings.

Special counsel has reported to the Department of Justice (DOJ) and the Securities and Exchange Commission the results of the investigation, and the company has entered into separate agreements with these two U.S. agencies to resolve the matters reported by special counsel. The company subsequently also entered into an agreement with the Federal Government of Nigeria (FGN) to resolve similar issues with the FGN. The company has previously reported the principal terms of these three agreements. Certain aspects of the agreement with the DOJ are set forth below.

Tidewater Marine International Inc. (“TMII”), a wholly-owned subsidiary of the company organized in the Cayman Islands, and the DOJ entered into a Deferred Prosecution Agreement (“DPA”). Pursuant to the DPA, the DOJ deferred criminal charges against TMII for a period of three years and seven days from the date of judicial approval of the Agreement, in return for: (a) TMII’s acceptance of responsibility for, and agreement not to contest or contradict the truthfulness of, the statement of facts and allegations contained in a three-count criminal information to be filed concurrently with the DPA; (b) TMII’s payment of a $7.35 million fine (which has been paid), (c) TMII’s and Tidewater Inc.’s compliance with certain undertakings relating to compliance with the FCPA and other applicable laws in connection with the company’s operations, and cooperation with domestic and foreign authorities in connection with the matters that are the subject of the DPA; (d) TMII’s and Tidewater Inc.’s agreement to continue to address any deficiencies in the company’s internal controls, policies and procedures relating to compliance with the FCPA and other applicable anti-corruption laws, if and to the extent not already addressed; and (e) Tidewater Inc.’s agreement to report to the DOJ in writing annually for the term of the DPA regarding remediation of the matters that are the subject of the DPA, the implementation of any enhanced internal controls, and any evidence of improper payments the company may have discovered during the term of the DPA. Implementation of the DOJ settlement eliminated a $3.0 million contingent civil penalty in connection with the SEC civil settlement detailed above. Tidewater submitted its first annual report to the DOJ in November 2011, its second annual report in November 2012, and its third annual report in October 2013.

If TMII and Tidewater Inc. comply with the DPA during its term, the DOJ will not bring the charges set out in the information. In the event TMII or Tidewater Inc. breaches the DPA, the DOJ has discretion to extend its term for up to a year, or bring certain criminal charges against TMII as outlined in the DPA. A federal district court accepted the DPA on November 9, 2010.

Merchant Navy Officers Pension Fund

After consultation with its advisers, on July 15, 2013, a subsidiary of the company was placed into administration in the United Kingdom. Joint administrators were appointed to administer and distribute the subsidiary’s assets to the subsidiary’s creditors. The vessels owned by the subsidiary have become aged and are no longer economical to operate, which has caused the subsidiary’s main business to decline in recent years. Only one vessel currently generates revenue and this vessel likely has a limited remaining operating window as an offshore service vessel. As part of the administration, the company agreed to acquire seven vessels and to waive certain intercompany claims. The purchase price valuation for the vessels, all but one of which are stacked, is based on independent, third party appraisals of the vessels.

The company has previously reported that a subsidiary of the company is a participating employer in an industry-wide multi-employer retirement fund in the United Kingdom, known as the Merchant Navy Officers Pension Fund (MNOPF). The subsidiary that participates in the MNOPF is the entity that has been placed into administration in the U.K. MNOPF is that subsidiary’s largest creditor, and has claimed as an unsecured creditor in the administration. The Company believes that the administration is in the best interests of the subsidiary and its principal stakeholders, including the MNOPF. The MNOPF has indicated that it does not object to the insolvency process and that, aside from asserting its claim in the subsidiary’s administration and based on the company’s representations of the financial status and other relevant aspects of the subsidiary, MNOPF will not pursue the subsidiary in connection with any amounts due or which may become due to the Fund. The administration is not expected to be fully complete for more than a year. The company believes that the administration will resolve the subsidiary’s participation in the MNOPF. The company believes that the ultimate resolution of this matter will not have a material effect on the consolidated financial statements.

Sonatide Joint Venture

The company has previously reported that it has been in negotiations with Sonangol regarding a new joint venture agreement for Sonatide, a joint venture between the company and Sonangol that serves the Angolan offshore energy industry. Pending the completion of the new agreement, the joint venture has been operating under a joint venture agreement, extended on several prior occasions, that was last extended through March 31, 2013. Based on the outcome of several meetings that were held during the June and September quarters, the company believes that the substantive issues between the parties have been resolved, and the company has drafted, with Sonangol’s input, a new definitive joint venture agreement that the company believes incorporates those understandings. The new definitive joint venture agreement, which has been executed by the company, is awaiting the signature of Sonangol’s authorized representatives. Accordingly, there is no agreement yet in place. In the interim, Sonatide continues its normal day-to-day operations consistent with the terms of the expired agreement without significant commercial or operational effects resulting from that expiration.

If negotiations relating to the Sonatide joint venture are ultimately unsuccessful, however, the company will work toward an orderly wind up of the joint venture. Based on prior conduct between the parties during this period of uncertainty, we believe that the joint venture would be allowed to honor existing vessel charter agreements through their contract terms. The global market for offshore supply vessels is currently reasonably well balanced, with offshore vessel supply approximately equal to offshore vessel demand; however, there would likely be negative financial impacts associated with the wind up of the existing joint venture and the possible redeployment of vessels to other markets, including mobilization costs and costs to redeploy Tidewater shore-based employees to other areas, in addition to lost revenues associated with potential downtime between vessel contracts. These financial impacts could, individually or in the aggregate, be material to our results of operations and cash flows for the periods when such costs would be incurred. If there is a need to redeploy vessels which are currently deployed in Angola to other international markets, Tidewater believes that there is sufficient demand for a majority of these vessels at prevailing market day rates.

During the six months ended September 30, 2013, the Sonatide joint venture entered into six new contracts with customers, all of which extend into 2014. During the twelve months ended September 30, 2013, the company redeployed vessels from its Angolan operations to other markets and also transferred vessels into its Angolan operations from other markets resulting in a net increase in the number of vessels operating in the area.

Tidewater and Sonangol have also continued to evaluate and discuss the impact of a new Foreign Exchange Law for the Angolan Petroleum Sector that became effective as of July 1, 2013. Under the new law, oil companies are required to make all payments for goods and services provided by foreign exchange residents in Angolan Kwanzas into an Angolan bank account. This new requirement could result in the joint venture collecting substantially all of its revenue in Angolan Kwanzas, unless a more efficient structure is agreed to by the joint venture parties. The conversion of Angolan Kwanzas into US Dollars and expatriation of the funds currently involves a lengthy process that results in time delays, currency fluctuation risk and conversion fees as well as possible additional taxes. The joint venture is working to design and implement procedures to conform to the recently enacted law and to develop more efficient cash collection processes; however, the successful implementation of any such processes depends on the new joint venture agreement becoming effective. As discussed below and under Liquidity, Capital Resources and Other Matters, over the last several quarters, the company has experienced a build-up in working capital that it has funded primarily by additional borrowings.

For the six months ended September 30, 2013, Tidewater’s Angolan operations generated vessel revenues of approximately $167.7 million, or 24%, of its consolidated vessel revenue, from an average of approximately 89 Tidewater-owned vessels that are marketed through the Sonatide joint venture (six of which were stacked on average during the six months ended September 30, 2013), and, for the six months ended September 30, 2012, generated vessel revenues of approximately $134.3 million, or 22%, of consolidated vessel revenue, from an average of approximately 86 Tidewater-owned vessels (11 of which were stacked on average during the six months ended September 30, 2012.

In addition to the company’s Angolan operations, which reflect the results of Tidewater-owned vessels marketed through the Sonatide joint venture (owned 49% by Tidewater), ten vessels and other assets are owned by the Sonatide joint venture. As of September 30, 2013 and March 31, 2013, the carrying value of Tidewater’s investment in the Sonatide joint venture, which is included in “Investments in, at equity, and advances to unconsolidated companies,” is approximately $53 million and $46 million, respectively.

Included in trade and other receivables at September 30, 2013 is approximately $280 million related to Sonatide, including cash received by Sonatide from customers and due to the company, costs paid by Tidewater on behalf of Sonatide and, finally, amounts due from customers which are expected to be remitted to the company through Sonatide after a new joint venture agreement is signed by Sonangol.

Included in accrued expenses at September 30, 2013 is approximately $70 million due to Sonatide for commissions payable (approximately $24 million) and other costs paid by Sonatide on behalf of the company.

Brazilian Customs

In April 2011, two Brazilian subsidiaries of Tidewater were notified by the Customs Office in Macae, Brazil that they were jointly and severally being assessed fines of 155.0 million Brazilian reais (approximately $68.6 million as of September 30, 2013). The assessment of these fines is for the alleged failure of these subsidiaries to obtain import licenses with respect to 17 Tidewater vessels that provided Brazilian offshore vessel services to Petrobras, the Brazilian national oil company, over a three-year period ending December 2009. After consultation with its Brazilian tax advisors, Tidewater and its Brazilian subsidiaries believe that vessels that provide services under contract to the Brazilian offshore oil and gas industry are deemed, under applicable law and regulations, to be temporarily imported into Brazil, and thus exempt from the import license requirement. The Macae Customs Office has, without a change in the underlying applicable law or regulations, taken the position that the temporary importation exemption is only available to new, and not used, goods imported into Brazil and therefore it was improper for the company to deem its vessels as being temporarily imported. The fines have been assessed based on this new interpretation of Brazilian customs law taken by the Macae Customs Office.

After consultation with its Brazilian tax advisors, the company believes that the assessment is without legal justification and that the Macae Customs Office has misinterpreted applicable Brazilian law on duties and customs. The company is vigorously contesting these fines (which it has neither paid nor accrued) and, based on the advice of its Brazilian counsel, believes that it has a high probability of success with respect to the overturn of the entire amount of the fines, either at the administrative appeal level or, if necessary, in Brazilian courts. In December 2011, an administrative board issued a decision that disallowed 149.0 million Brazilian reais (approximately $65.9 million as of September 30, 2013) of the total fines sought by the Macae Customs Office. In two separate proceedings in 2013, a secondary administrative appeals board considered fines totaling 127.0 million Brazilian reais (approximately $56.2 million as of September 30, 2013) and rendered decisions that disallowed all of those fines. The remaining fines totaling 28.0 million Brazilian reais (approximately $12.4 million as of September 30, 2013) are still subject to a secondary administrative appeals board hearing, but the company believes that both decisions will be helpful in that upcoming hearing. The secondary board decisions disallowing the fines totaling 127.0 million Brazilian reais are, however, still subject to the possibility of further administrative appeal by the authorities that imposed the initial fines. The company believes that the ultimate resolution of this matter will not have a material effect on the consolidated financial statements.

Potential for Future Brazilian State Tax Assessment

The company is aware that a Brazilian state in which the company has operations has notified two of the company’s competitors that they are liable for unpaid taxes (and penalties and interest thereon) for failure to pay state import taxes with respect to vessels that such competitors operate within the coastal waters of such state pursuant to charter agreements. The import tax being asserted is equal to a percentage (which could be as high as 16% for vessels entering that state’s waters prior to December 31, 2010 and 3% thereafter) of the affected vessels’ declared values. The company understands that the two companies involved are contesting the assessment through administrative proceedings before the taxing authority.

The company’s two Brazilian subsidiaries have not been similarly notified by the Brazilian state that they have an import tax liability related to their vessel activities imported through that state. Although the company has been advised by its Brazilian tax counsel that substantial defenses would be available if a similar tax claim were asserted against the company, if an import tax claim were to be asserted, it could be for a substantial amount given that the company has had substantial and continuing operations within the territory of the state (although the amount could fluctuate significantly depending on the administrative determination of the taxing authority as to the rate to apply, the vessels subject to the levy and the time periods covered). In addition, under certain circumstances, the company might be required to post a bond or other adequate security in the amount of the assessment (plus any interest and penalties) if it became necessary to challenge the assessment in a Brazilian court. The statute of limitations for the Brazilian state to levy an assessment of the import tax is five years from the date of a vessel’s entry into Brazil. The company has not yet determined the potential tax assessment, and according to the Brazilian tax counsel, chances of defeating a possible claim/notification from the State authorities in court are probable. To obtain legal certainty and predictability for future charter agreements and because the company has imported several vessels to start new charters in Brazil, the company filed several suits in 2011, 2012 and 2013, against the Brazilian state and has deposited (or, in recent cases, is in the process of depositing) the respective state tax for these newly imported vessels. As of September 30, 2013, no accrual has been recorded for any liability associated with any potential future assessment for previous periods based on management’s assessment, after consultation with Brazilian counsel, that a liability for such taxes was not probable.

Nigeria Marketing Agent Litigation

On March 1, 2013, Tidewater filed suit in the London Commercial Court against Tidewater’s Nigerian marketing agent for breach of the agent’s obligations under contractual agreements between the parties. The alleged breach involves actions of the Nigerian marketing agent to discourage various affiliates of TOTAL S.A. from paying approximately $19 million due to the company for vessel services performed in Nigeria. Shortly after the London Commercial Court filing, TOTAL commenced interpleader proceedings in Nigeria naming the Nigerian agent and the company as respondents and seeking an order which would allow TOTAL to deposit those monies with a Nigerian court for the respondents to resolve. On April 25, 2013, Tidewater filed motions in the Nigerian Federal High Court to stop the interpleader proceedings in Nigeria or alternatively stay them until the resolution of the suit filed in London. The company will continue to actively pursue the collection of those monies. On April 30, 2013, the Nigerian marketing agent filed a separate suit in the Nigerian Federal High Court naming Tidewater and certain TOTAL affiliates as defendants. The suit seeks various declarations and orders, including a claim for the monies that are subject to the above interpleader proceedings, and other relief. The company is seeking dismissal of this suit and otherwise intends to vigorously defend against the claims made. The company has not reserved for this receivable and believes that the ultimate resolution of this matter will not have a material effect on the consolidated financial statements.

In October, 2012, Tidewater had notified the Nigerian marketing agent that it was discontinuing its relationship with the Nigerian marketing agent. The company has entered into a new strategic relationship with a different Nigerian counterparty that it believes will better serve the company’s long term interests in Nigeria. This new strategic relationship is currently functioning as the company intended.

Venezuelan Operations

On February 16, 2010, Tidewater and certain of its subsidiaries (collectively, the “Claimants”) filed with the International Centre for Settlement of Investment Disputes (“ICSID”) a Request for Arbitration against the Bolivarian Republic of Venezuela. As previously reported by Tidewater, in May 2009 Petróleos de Venezuela, S.A. (“PDVSA”), the national oil company of Venezuela, took possession and control of (a) eleven of the Claimants’ vessels that were then supporting PDVSA operations in Lake Maracaibo, (b) the Claimants’ shore-based headquarters adjacent to Lake Maracaibo, (c) the Claimants’ operations in Lake Maracaibo, and (d) certain other related assets. The company also previously reported that in July 2009 Petrosucre, S.A., a subsidiary of PDVSA, took possession and control of the Claimants’ four vessels, operations, and related assets in the Gulf of Paria. It is Tidewater’s position that, through those measures, the Republic of Venezuela directly or indirectly expropriated the Claimants’ investments, including the capital stock of the Claimants’ principal operating subsidiary in Venezuela.

The Claimants alleged in the Request for Arbitration that each of the measures taken by the Republic of Venezuela against the Claimants violates the Republic of Venezuela’s obligations under the bilateral investment treaty with Barbados and rules and principles of Venezuelan law and international law. An arbitral tribunal was constituted under the ICSID Convention to resolve the dispute. The tribunal first addressed the Republic of Venezuela’s objections to the tribunal’s jurisdiction over the dispute. After two rounds of briefing by the parties, a hearing on jurisdiction was held in Washington, D.C. on February 29 and March 1, 2012.

On February 8, 2013, the tribunal issued its decision on jurisdiction. The tribunal found that it has jurisdiction over the claims under the Venezuela-Barbados bilateral investment treaty, including the claim for compensation for the expropriation of Tidewater’s principal operating subsidiary, but that it does not have jurisdiction based on Venezuela’s investment law. The practical effect of the tribunal’s decision is to exclude from the case the claims for expropriation of the fifteen vessels described above. The proceeding will now move to the merits, including a determination whether the Republic of Venezuela violated the Venezuela-Barbados bilateral investment treaty and a valuation of Tidewater’s principal operating subsidiary in Venezuela. At the time of the expropriation, the principal operating subsidiary had sizeable accounts receivable from PDVSA and Petrosucre, denominated in both U.S. Dollars and Venezuelan Bolivars. The company expects those accounts receivable to form part of the total valuation of Tidewater’s principal operating subsidiary. As a result of the seizures, the lack of further operations in Venezuela, and the continuing uncertainty about the timing and amount of the compensation the company might collect in the future, the company recorded a $44.8 million provision during the quarter ended June 30, 2009, to fully reserve accounts receivable due from PDVSA and Petrosucre.

While the tribunal determined that it does not have jurisdiction over the claim for the seizure of the fifteen vessels, Tidewater received during fiscal 2011 insurance proceeds for the insured value of those vessels (less an additional premium payment triggered by those proceeds). Tidewater believes that the claims remaining in the case, over which the tribunal upheld jurisdiction, represent the most substantial portion of the overall value lost as a result of the measures taken by the Republic of Venezuela. Tidewater has discussed the nature of the insurance proceeds received for the fifteen vessels in previous quarterly and annual filings.

The tribunal has issued a briefing and hearing schedule to determine the merits of the claims over which the tribunal has jurisdiction. That schedule culminates in a final hearing in mid-2014.

Legal Proceedings

Various legal proceedings and claims are outstanding which arose in the ordinary course of business. In the opinion of management, the amount of ultimate liability, if any, with respect to these actions, will not have a material adverse effect on the company’s financial position, results of operations, or cash flows.

Fair_Value_Measurements

Fair Value Measurements	6 Months Ended
Fair Value Measurements	Sep. 30, 2013
Fair Value Measurements	'
	-9	FAIR VALUE MEASUREMENTS
	The company follows the provisions of ASC 820, Fair Value Measurements and Disclosures, for financial assets and liabilities that are measured and reported at fair value on a recurring basis. ASC 820 establishes a hierarchy for inputs used in measuring fair value. Fair value is calculated based on assumptions that market participants would use in pricing assets and liabilities and not on assumptions specific to the entity. The statement requires that each asset and liability carried at fair value be classified into one of the following categories:
	Level 1: Quoted market prices in active markets for identical assets or liabilities
	Level 2: Observable market based inputs or unobservable inputs that are corroborated by market data
	Level 3: Unobservable inputs that are not corroborated by market data
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	The company measures on a recurring basis and records at fair value investments held by participants in a supplemental executive retirement plan. The following table provides the fair value hierarchy for the plan assets measured at fair value as of September 30, 2013:


	(In thousands)		Total				Quoted prices in				Significant			Significant
							active markets				observable			unobservable
							(Level 1)				inputs			inputs
											(Level 2)			(Level 3)
	Equity securities:
	Common stock		$	4,039				4,039				---			---
	Preferred stock			---				---				---			---
	Foreign stock			316				316				---			---
	American depository receipts			1,697				1,697				---			---
	Preferred American depository receipts			13				13				---			---
	Real estate investment trusts			---				---				---			---
	Debt securities:
	Government debt securities			1,786				1,114				672			---
	Open ended mutual funds			1,563				1,563				---			---
	Cash and cash equivalents			1,032				401				631			---

	Total		$	10,446				9,143				1,303			---
	Other pending transactions			(264	)			(264	)			---			---

	Total fair value of plan assets		$	10,182				8,879				1,303			---

	The following table provides the fair value hierarchy for the plan assets measured at fair value as of March 31, 2013:


	(In thousands)		Total				Quoted prices in				Significant			Significant
							active markets				observable			unobservable
							(Level 1)				inputs			inputs
											(Level 2)			(Level 3)
	Equity securities:
	Common stock		$	4,240				4,240				---			---
	Preferred stock			---				---				---			---
	Foreign stock			285				285				---			---
	American depository receipts			1,811				1,811				---			---
	Preferred American depository receipts			16				16				---			---
	Real estate investment trusts			---				---				---			---
	Debt securities:
	Government debt securities			2,007				1,240				767			---
	Open ended mutual funds			1,743				1,743				---			---
	Cash and cash equivalents			533				93				440			---

	Total		$	10,635				9,428				1,207			---
	Other pending transactions			(149	)			(149	)			---			---

	Total fair value of plan assets		$	10,486				9,279				1,207			---


	Other Financial Instruments
	The company’s primary financial instruments consist of cash and cash equivalents, trade receivables and trade payables with book values that are considered to be representative of their respective fair values. The company periodically utilizes derivative financial instruments to hedge against foreign currency denominated assets and liabilities, currency commitments, or to lock in desired interest rates. These transactions are generally spot or forward currency contracts or interest rate swaps that are entered into with major financial institutions. Derivative financial instruments are intended to reduce the company’s exposure to foreign currency exchange risk and interest rate risk. The company enters into derivative instruments only to the extent considered necessary to address its risk management objectives and does not use derivative contracts for speculative purposes. The derivative instruments are recorded at fair value using quoted prices and quotes obtainable from the counterparties to the derivative instruments.
	Cash Equivalents. The company’s cash equivalents, which are securities with maturities less than 90 days, are held in money market funds or time deposit accounts with highly rated financial institutions. The carrying value for cash equivalents is considered to be representative of its fair value due to the short duration and conservative nature of the cash equivalent investment portfolio.
	Spot Derivatives. Spot derivative financial instruments are short-term in nature and generally settle within two business days. The fair value of spot derivatives approximates the carrying value due to the short-term nature of this instrument, and as a result, no gains or losses are recognized.
	The company had no outstanding foreign exchange spot contracts at September 30, 2013 and March 31, 2013.
	Forward Derivatives. Forward derivative financial instruments are generally longer-term in nature but generally do not exceed one year. The accounting for gains or losses on forward contracts is dependent on the nature of the risk being hedged and the effectiveness of the hedge. Forward contracts are valued using counterparty quotations, and we validate the information obtained from the counterparties in calculating the ultimate fair values using the market approach and obtaining broker quotations. As such, these derivative contracts are classified as Level 2.
	At September 30, 2013, the company had one British pound forward contract outstanding. The forward contract has an expiration date of December 18, 2013. The change in fair value of the forward contract was immaterial and was recorded as a foreign exchange gain during quarter ended September 30, 2013. The forward contract did not qualify as a hedge instrument; therefore, all changes in fair value of the forward contract were recorded in earnings.
	At March 31, 2013, the company had three British pound forward contracts outstanding, which were generally intended to hedge the company’s foreign exchange exposure relating to its MNOPF liability as disclosed in Note (8) and elsewhere in this document. The forward contracts expired at various times through December 18, 2013. The combined change in fair value of the forward contracts was immaterial and was recorded as a foreign exchange loss during the fiscal year ended March 31, 2013, because the forward contracts did not qualify as hedge instruments. All changes in fair value of the forward contracts were recorded in earnings.
The following table provides the fair value hierarchy for the company’s other financial instruments measured as of September 30, 2013:


(In thousands)		Total				Quoted prices in				Significant			Significant
						active markets				observable			unobservable
						(Level 1)				inputs			inputs
										(Level 2)			(Level 3)
Cash equivalents		$	376				376				---			---
Long-term British pound forward derivative contracts			1,132				---				1,132			---

Total fair value of assets		$	1,508				376				1,132			---


The following table provides the fair value hierarchy for the company’s other financial instruments measured as of March 31, 2013:


(In thousands)		Total				Quoted prices in				Significant			Significant
						active markets				observable			unobservable
						(Level 1)				inputs			inputs
										(Level 2)			(Level 3)
Cash equivalents		$	949				949				---			---
Long-term British pound forward derivative contracts			4,359				---				4,359			---

Total fair value of assets		$	5,308				949				4,359			---

Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis
Asset Impairments
The company accounts for long-lived assets in accordance with ASC 360-10-35, Impairment or Disposal of Long-Lived Assets. The company reviews the vessels in its active fleet for impairment whenever events occur or changes in circumstances indicate that the carrying amount of an asset group may not be recoverable. In such evaluation the estimated future undiscounted cash flows generated by an asset group are compared with the carrying amount of the asset group to determine if a write-down may be required. With respect to vessels that have not been stacked, we group together for impairment testing purposes vessels with similar operating and marketing characteristics. We also subdivide our groupings of assets with similar operating and marketing characteristics between our older vessels and newer vessels.
The company estimates cash flows based upon historical data adjusted for the company’s best estimate of expected future market performance, which, in turn, is based on industry trends. If an asset group fails the undiscounted cash flow test, the company uses the discounted cash flow method to determine the estimated fair value of each asset group and compares such estimated fair value (considered Level 3, as defined by ASC 360) to the carrying value of each asset group in order to determine if impairment exists. If impairment exists, the carrying value of the asset group is reduced to its estimated fair value.
In addition to the periodic review of its active long-lived assets for impairment when circumstances warrant, the company also performs a review of its stacked vessels and vessels withdrawn from service every six months or whenever changes in circumstances indicate that the carrying amount of a vessel may not be recoverable. Management estimates each stacked vessel’s fair value by considering items such as the vessel’s age, length of time stacked, likelihood of a return to active service, actual recent sales of similar vessels, which are unobservable inputs. In certain situations we obtain an estimate of the fair value of the stacked vessel from third-party appraisers or brokers. The company records an impairment charge when the carrying value of a vessel withdrawn from service or a stacked vessel exceeds its estimated fair value. The estimates of fair value of stacked vessels are also subject to significant variability, are sensitive to changes in market conditions, and are reasonably likely to change in the future.
The below table summarizes the combined fair value of the assets that incurred impairments during the quarters and six-month periods ended September 30, 2013 and 2012, along with the amount of impairment. The impairment charges were recorded in gain on asset dispositions, net.


		Quarter Ended								Six Months Ended
		September 30,								September 30,
(In thousands)		2013				2012				2013			2012
Amount of impairment incurred		$	175				790				4,047			3,564
Combined fair value of assets incurring impairment			161				1,192				4,466			8,602

Other_Assets_Accrued_Expenses_

Other Assets, Accrued Expenses, Other Current Liabilities and Other Liabilities and Deferred Credits	6 Months Ended
	Sep. 30, 2013
Other Assets, Accrued Expenses, Other Current Liabilities and Other Liabilities and Deferred Credits	'
	-10	OTHER ASSETS, ACCRUED EXPENSES, OTHER CURRENT LIABILITIES AND OTHER LIABILITIES AND DEFERRED CREDITS
	A summary of other assets at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)		September 30,		March 31,
	(In thousands)		2013		2013
	Recoverable insurance losses		$	9,870		10,833
	Deferred income tax assets			82,328		73,105
	Deferred finance charges			8,161		5,133
	Savings plans and supplemental plan			22,026		23,149
	Noncurrent tax receivable			9,106		9,106
	Other			17,748		4,951

			$	149,239		126,277

	A summary of accrued expenses at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)		September 30,		March 31,
	(In thousands)		2013		2013
	Payroll and related payables		$	21,747		23,453
	Commissions payable			31,378		13,866
	Accrued vessel expenses			103,098		103,177
	Accrued interest expense			5,443		8,096
	Other accrued expenses			6,519		10,494

			$	168,185		159,086

	A summary of other current liabilities at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)		September 30,		March 31,
	(In thousands)		2013		2013
	Taxes payable		$	38,205		38,100
	Deferred credits - current			649		1,374
	Dividend payable			480		334

			$	39,334		39,808

	A summary of other liabilities and deferred credits at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)		September 30,		March 31,
	(In thousands)		2013		2013
	Postretirement benefits liability		$	26,939		27,681
	Pension liabilities			39,332		37,096
	Deferred gain on vessel sales			71,544		39,568
	Other			36,555		34,729

			$	174,370		139,074

Accounting_Pronouncements

Accounting Pronouncements	6 Months Ended
	Sep. 30, 2013
Accounting Pronouncements	'
	-11	ACCOUNTING PRONOUNCEMENTS
	From time to time new accounting pronouncements are issued by the FASB that are adopted by the company as of the specified effective date. Unless otherwise discussed, management believes that the impact of recently issued standards, which are not yet effective, will not have a material impact on the company’s consolidated financial statements upon adoption.
	In February 2013, the FASB issued ASU 2013-02 Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. This guidance requires entities to present changes in accumulated other comprehensive income by component, including the amounts of changes that are due to reclassifications and the amounts that are due to current period other comprehensive income. Entities are also required to present significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income. The new guidance was effective for us beginning April 1, 2013 and includes disclosure changes only.

Segment_and_Geographic_Distrib

Segment and Geographic Distribution of Operations	6 Months Ended
Segment and Geographic Distribution of Operations	Sep. 30, 2013
Segment and Geographic Distribution of Operations	'
	-12	SEGMENT AND GEOGRAPHIC DISTRIBUTION OF OPERATIONS
	The company follows the disclosure requirements of ASC 280, Segment Reporting. Operating business segments are defined as a component of an enterprise for which separate financial information is available and is evaluated by the chief operating decision maker in deciding how to allocate resources and in assessing performance. We manage and measure our business performance in four distinct operating segments: Americas, Asia/Pacific, Middle East/North Africa, and Sub-Saharan Africa/Europe. These segments are reflective of how the company’s chief operating decision maker (CODM) reviews operating results for the purposes of allocating resources and assessing performance. The company’s CODM is its Chief Executive Officer.
	The following table provides a comparison of revenues, vessel operating profit, depreciation and amortization, and additions to properties and equipment for the quarters and six-month periods ended September 30, 2013 and 2012. Vessel revenues and operating costs relate to vessels owned and operated by the company while other operating revenues relate to the activities of the company’s shipyards, brokered vessels and other miscellaneous marine-related businesses.


			Quarter Ended								Six Months Ended
			September 30,								September 30,
	(In thousands)		2013				2012				2013				2012
	Revenues:
	Vessel revenues:
	Americas		$	101,929				82,316				192,173				159,966
	Asia/Pacific			37,430				45,738				80,386				97,480
	Middle East/N. Africa			45,370				32,051				86,583				64,501
	Sub-Saharan Africa/Europe			178,939				149,717				336,156				277,969

				363,668				309,822				695,298				599,916
	Other operating revenues			4,269				2,096				6,724				6,450

			$	367,937				311,918				702,022				606,366

	Vessel operating profit:
	Americas		$	23,675				9,506				43,976				19,698
	Asia/Pacific			4,807				7,826				15,096				22,734
	Middle East/N. Africa			13,446				6,280				23,569				12,562
	Sub-Saharan Africa/Europe			47,261				44,330				64,780				71,426

				89,189				67,942				147,421				126,420
	Corporate expenses			(12,891	)			(12,484	)			(29,446	)			(22,951	)
	Gain on asset dispositions, net			49				1,833				2,189				2,671
	Other operating expense			218				(94	)			(174	)			544

	Operating income		$	76,565				57,197				119,990				106,684

	Foreign exchange gain (loss)			3,017				529				2,928				(1,222	)
	Equity in net earnings of unconsolidated companies			3,781				3,357				8,201				5,720
	Interest income and other, net			538				1,128				1,278				1,847
	Loss on early extinguishment of debt			(4,144	)			---				(4,144	)			---
	Interest and other debt costs			(9,918	)			(7,148	)			(18,831	)			(14,735	)

	Earnings before income taxes		$	69,839				55,063				109,422				98,294

	Depreciation and amortization:
	Americas		$	10,833				10,629				20,945				20,721
	Asia/Pacific			4,122				4,833				8,647				9,946
	Middle East/N. Africa			5,731				4,388				11,337				8,467
	Sub-Saharan Africa/Europe			20,581				15,309				39,736				30,802
	Corporate			789				888				1,499				1,895

			$	42,056				36,047				82,164				71,831

	Additions to properties and equipment:
	Americas		$	8,845				25,118				12,039				41,896
	Asia/Pacific			453				5,071				968				5,165
	Middle East/N. Africa			770				721				909				1,795
	Sub-Saharan Africa/Europe (A)			8,086				36,659				344,557				48,534
	Corporate (B)			49,747				44,194				111,597				88,285

			$	67,901				111,763				470,070				185,675


	(A)	Included in Sub-Saharan Africa/Europe for the six months ended September 30, 2013 is $245.6 million related to vessels acquired through the acquisition of Troms Offshore.

	(B)	Included in Corporate are additions to properties and equipment relating to vessels currently under construction which have not yet been assigned to a non-corporate reporting segment as of the dates presented.

The following table provides a comparison of total assets at September 30, 2013 and March 31, 2013:


(In thousands)		September 30,				March 31,
(In thousands)		2013				2013
Total assets:
Americas		$	930,475				885,470
Asia/Pacific			487,850				607,546
Middle East/North Africa			584,805				507,124
Sub-Saharan Africa/Europe			2,214,683				1,706,355

			4,217,813				3,706,495
Investments in, at equity, and advances to unconsolidated companies			52,254				46,047

			4,270,067				3,752,542
Corporate (A)			484,512				415,513

		$	4,754,579				4,168,055

Note A: Included in Corporate are vessels currently under construction which have not yet been assigned to a non-corporate reporting segment. The vessel construction costs will be reported in Corporate until the earlier of the vessels being assigned to a non-corporate reporting segment or the vessels’ delivery. At September 30, 2013 and March 31, 2013, $306.7 million and $229.3 million, respectively, of vessel construction costs are included in Corporate.
The following table discloses the amount of revenue by segment, and in total for the worldwide fleet, along with the respective percentage of total vessel revenue for the quarters and six-month periods ended September 30, 2013 and 2012:


Revenue by vessel class		Quarter Ended September 30,																Six Months Ended September 30,
(In thousands)		2013				%				2012				%				2013		%		2012		%
Americas fleet:
Deepwater vessels		$	61,811				17%				44,747				14%				116,843		17%		81,027		14%
Towing-supply/supply			30,861				8%				31,109				10%				58,531		8%		65,461		11%
Other			9,257				3%				6,460				2%				16,799		3%		13,478		2%
Total		$	101,929				28%				82,316				27%				192,173		28%		159,966		27%
Asia/Pacific fleet:
Deepwater vessels		$	19,923				5%				24,592				8%				44,215		6%		49,929		8%
Towing-supply/supply			16,559				5%				20,229				7%				34,281		5%		45,729		8%
Other			948				<1%				917				<1%				1,890		<1%		1,822		<1%
Total		$	37,430				10%				45,738				15%				80,386		11%		97,480		16%
Middle East/N. Africa fleet:
Deepwater vessels		$	15,732				5%				12,275				4%				31,584		5%		23,559		4%
Towing-supply/supply			28,763				8%				18,859				6%				53,260		8%		38,859		6%
Other			875				<1%				917				<1%				1,739		<1%		2,083		<1%
Total		$	45,370				13%				32,051				10%				86,583		13%		64,501		10%
Sub-Saharan Africa/Europe fleet:
Deepwater vessels		$	106,541				29%				67,696				22%				193,792		28%		130,311		22%
Towing-supply/supply			56,772				16%				63,548				20%				111,632		16%		112,560		20%
Other			15,626				4%				18,473				6%				30,732		4%		35,098		6%
Total		$	178,939				49%				149,717				48%				336,156		48%		277,969		47%
Worldwide fleet:
Deepwater vessels		$	204,007				56%				149,310				48%				386,434		56%		284,826		47%
Towing-supply/supply			132,955				37%				133,745				43%				257,704		37%		262,609		44%
Other			26,706				7%				26,767				9%				51,160		7%		52,481		9%
Total		$	363,668				100%				309,822				100%				695,298		100%		599,916		100%

Goodwill

Goodwill	6 Months Ended
Goodwill	Sep. 30, 2013
Goodwill	'
	-13	GOODWILL
	The company tests goodwill for impairment annually at the reporting unit level using carrying amounts as of December 31 or more frequently if events and circumstances indicate that goodwill might be impaired.
	The company performed its annual goodwill impairment assessment during the quarter ended December 31, 2012 and determined there was no goodwill impairment.
	During the first six months ended September 30, 2013, $42.2 million of goodwill related to the acquisition of Troms Offshore was allocated to the Sub-Saharan Africa/Europe segment.
	Goodwill by reportable segment at September 30, 2013 and at March 31, 2013 is as follows:


	(In thousands)		September 30,		March 31,
	(In thousands)		2013		2013
	Americas		$	114,237		114,237
	Asia/Pacific			56,283		56,283
	Sub-Saharan Africa/Europe			169,462		127,302

			$	339,982		297,822

SaleLeaseback_Arrangements

Sale/Leaseback Arrangements	6 Months Ended
Sale/Leaseback Arrangements	Sep. 30, 2013
Sale/Leaseback Arrangements	'
	-14	SALE/LEASEBACK ARRANGEMENTS
	In September 2013, the company sold two vessels to an unrelated third party, and simultaneously entered into bareboat charter agreements with the purchaser. The sale/leaseback transactions resulted in proceeds to the company of $65.6 million and a deferred gain of $31.3 million. The aggregate carrying value of the two vessels was $34.3 million at the dates of sale. The leases on the vessels will expire on September 30, 2020 and the company has the option to extend each respective bareboat charter agreement for a period of 24 months.
	The company is accounting for the transactions as sale/leaseback transactions with operating lease treatment and expenses lease payments over the seven year lease terms. The deferred gains will be amortized to gain on asset dispositions, net ratably over the lease term.
	Under each sale/leaseback agreement, the company has the right to either re-acquire the two vessels at approximately 55% of the original sales price at the end of the sixth year, deliver the vessel to the owner at the end of the lease term, or extend the lease for 24 months at mutually agreeable lease rates. Any deferred gain balance remaining upon the repurchase of the vessel will reduce the vessels’ stated cost after exercising the purchase option.
	As of September 30, 2013, the future minimum lease payments for these two vessels under the operating lease terms are as follows:


	Fiscal year ending		Amount
	Fiscal year ending		(In thousands)
	Remaining six-months of 2014		$	2,794
	2015			5,588
	2016			5,589
	2017			5,589
	2018			6,830
	Thereafter			17,076

	Total future lease payments		$	43,466

Acquisition_Tables

Acquisition (Tables)	6 Months Ended
Acquisition (Tables)	Sep. 30, 2013
Allocation of Purchase Price for Acquisition	'
	The following table summarizes the allocation of the purchase price for the acquisition of Troms Offshore:


	(In thousands)
	Cash	$	22,263
	Trade receivables and other current assets		9,816
	Vessels		245,605
	Goodwill		42,160
	Payable and other liabilities		(13,020	)
	Notes payable		(156,824	)

	Total purchase price	$	150,000

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	6 Months Ended
Stockholders' Equity (Tables)	Sep. 30, 2013
Schedule of Common Stock Repurchased and Average Price Paid Per Share	'
	The aggregate dollar outlay for common stock repurchased, along with number of shares repurchased, and average price paid per share, for the quarters and six-month periods ended September 30 is as follows:


		Quarter Ended							Six Months Ended
		September 30,							September 30,
	(In thousands, except share and per share data)	2013			2012				2013				2012
	Aggregate dollar outlay for common stock repurchased	$	---			---				---				65,028
	Shares of common stock repurchased		---			---				---				1,400,500
	Average price paid per common share	$	---			---				---				46.43

Schedule of Dividends Declared	'
	The Board of Directors declared the following dividends for the quarters and six-month periods ended September 30:


		Quarter Ended							Six Months Ended
		September 30,							September 30,
	(In thousands, except dividend per share)	2013			2012				2013				2012
	Dividends declared	$	12,536			12,544				25,035				25,169
	Dividend per share		0.25			0.25				0.5				0.5

Changes in Accumulated Other Comprehensive Income by Component, Net of Tax	'
	The changes in accumulated other comprehensive income by component, net of tax for the quarters and six month periods ended September 30, 2013 and 2012 are as follows:


		For the quarter ended September 30, 2013																	For the six months ended September 30, 2013
	(in thousands)	Balance			Gains/				Reclasses				Net			Remaining			Balance			Gains/			Reclasses		Net			Remaining
		at			(losses)				from OCI				period			balance			at			(losses)			from OCI		period			balance
		6/30/13			recognized				to net				OCI			9/30/13			3/31/13			recognized			to net		OCI			9/30/13
					in OCI				income													in OCI			income
	Available for sale securities		(10	)		(237	)			64				(173	)		(183	)		(121	)		(206	)		144		(62	)		(183	)
	Currency translation adjustment		(9,811	)		---				---				---			(9,811	)		(9,811	)		---			---		---			(9,811	)
	Pension/Post-retirement benefits		(4,353	)		---				---				---			(4,353	)		(4,353	)		---			---		---			(4,353	)
	Interest rate swaps		(2,739	)		---				116				116			(2,623	)		(2,856	)		---			233		233			(2,623	)

	Total		(16,913	)		(237	)			180				(57	)		(16,970	)		(17,141	)		(206	)		377		171			(16,970	)


		For the quarter ended September 30, 2012																	For the six months ended September 30, 2012
	(in thousands)	Balance			Gains/				Reclasses				Net			Remaining			Balance			Gains/			Reclasses		Net			Remaining
		at			(losses)				from OCI				period			balance			at			(losses)			from OCI		period			balance
		6/30/12			recognized				to net				OCI			9/30/12			3/31/12			recognized			to net		OCI			9/30/12
					in OCI				income													in OCI			income
	Available for sale securities		(373	)		410				9				419			46			251			(351	)		146		(205	)		46
	Currency translation adjustment		(9,811	)		---				---				---			(9,811	)		(9,811	)		---			---		---			(9,811	)
	Pension/Post-retirement benefits		(6,448	)		---				---				---			(6,448	)		(6,448	)		---			---		---			(6,448	)
	Interest rate swaps		(3,206	)		---				117				117			(3,089	)		(3,322	)		---			233		233			(3,089	)

	Total		(19,838	)		410				126				536			(19,302	)		(19,330	)		(351	)		379		28			(19,302	)

Reclassifications from Accumulated Other Comprehensive Loss to Condensed Consolidated Statement of Income	'
	The following table summarizes the reclassifications from accumulated other comprehensive loss to the condensed consolidated statement of income for the quarters and six month periods ended September 30, 2013 and 2012:


		Quarter Ended									Six Months Ended								Affected line item in the condensed
		September 30,									September 30,								consolidated statements of income
	(In thousands)	2013					2012				2013					2012
	Realized gains on available for-sale securities	$	99					15				222					225		Interest income and other, net
	Amortization of interest rate swap		178					180				358					358		Interest and other debt costs

	Total pre-tax amounts		277					195				580					583
	Tax effect		97					68				203					204

	Total gains for the period, net of tax	$	180					127				377					379

Income_Taxes_Tables

Income Taxes (Tables)	6 Months Ended
Income Taxes (Tables)	Sep. 30, 2013
Schedule of Effective Tax Rate Applicable to Pre-Tax Earnings	'
	The effective tax rate applicable to pre-tax earnings, for the quarters and the six-month periods ended September 30, is as follows:


		Quarter Ended						Six Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
	Effective tax rate applicable to pre-tax earnings		22.4	%		24.9	%		23	%		24.5	%

Schedule of Uncertain Tax Positions and Income Tax Payable	'
	The company’s balance sheet at September 30, 2013 reflects the following in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 740, Income Taxes:


	(In thousands)	September 30,
	(In thousands)	2013
	Tax liabilities for uncertain tax positions	$	16,304
	Income tax payable		32,787

Schedule of Unrecognized Tax Benefits Which Would Lower Effective Tax Rate if Realized	'
	Unrecognized tax benefits, which would lower the effective tax rate if realized at September 30, 2013, are as follows:


	(In thousands)	September 30,
	(In thousands)	2013
	Unrecognized tax benefit related to state tax issues	$	8,202
	Interest receivable on unrecognized tax benefit related to state tax issues		20

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	6 Months Ended
Employee Benefit Plans (Tables)	Sep. 30, 2013
Schedule of Carrying Value of Trust Assets, Including Unrealized Gains or Losses	'
	The following table summarizes the carrying value of the trust assets, including unrealized gains or losses at September 30, 2013 and March 31, 2013:


	(In thousands)	September 30,			March 31,
	(In thousands)	2013			2013
	Investments held in Rabbi Trust	$	10,182			10,486
	Unrealized gains (losses) in fair value of trust assets		(183	)		(121	)
	Unrealized gains (losses) in fair value of trust assets are net of income tax expense of		(98	)		(65	)
	Obligations under the supplemental plan		22,260			21,431

Schedule of Net Periodic Benefit Cost	'
	The net periodic benefit cost for the company’s U.S. defined benefit pension plan and the supplemental plan (referred to collectively as “Pension Benefits”) and the postretirement health care and life insurance plan (referred to collectively as “Other Benefits”) is comprised of the following components:


		Quarter Ended						Six Months Ended
		September 30,						September 30,
	(In thousands)	2013			2012			2013			2012
	Pension Benefits:
	Service cost	$	198			273			396			546
	Interest cost		895			1,072			1,790			2,144
	Expected return on plan assets		(718	)		(687	)		(1,436	)		(1,374	)
	Amortization of prior service cost		12			12			24			24
	Recognized actuarial loss		276			448			552			896

	Net periodic benefit cost	$	663			1,118			1,326			2,236

	Other Benefits:
	Service cost	$	101			119			202			238
	Interest cost		262			309			524			618
	Amortization of prior service cost		(508	)		(508	)		(1,016	)		(1,016	)
	Recognized actuarial (gain) loss		(99	)		---			(198	)		---

	Net periodic benefit cost	$	(244	)		(80	)		(488	)		(160	)

Indebtedness_Tables

Indebtedness (Tables)	6 Months Ended
Indebtedness (Tables)	Sep. 30, 2013
Debt Costs	'
	Interest and debt costs incurred, net of interest capitalized, for the quarters and the six-month periods ended September 30, are as follows:


		Quarter Ended						Six Months Ended
		September 30,						September 30,
	(In thousands)	2013			2012			2013		2012
	Interest and debt costs incurred, net of interest capitalized	$	9,918			7,148			18,831		14,735
	Interest costs capitalized		2,636			2,913			5,598		5,736

	Total interest and debt costs	$	12,554			10,061			24,429		20,471

September 2010 Senior Notes	'
Schedule of Aggregate Amount of Senior Unsecured Notes Outstanding	'
	September 2010 Senior Notes
	In fiscal 2011, the company completed the sale of $425 million of senior unsecured notes. A summary of the aggregate amount of these notes outstanding at September 30, 2013 and March 31, 2013, is as follows:


	(In thousands, except weighted average data)	September 30,			March 31,
	(In thousands, except weighted average data)	2013			2013
	Aggregate debt outstanding	$	425,000			425,000
	Weighted average remaining life in years		6.1			6.6
	Weighted average coupon rate on notes outstanding		4.25	%		4.25	%
	Fair value of debt outstanding		436,530			458,520

July 2003 Senior Notes	'
Schedule of Aggregate Amount of Senior Unsecured Notes Outstanding	'
	July 2003 Senior Notes
	In July 2003, the company completed the sale of $300 million of senior unsecured notes. A summary of the aggregate amount of remaining senior unsecured notes outstanding at September 30, 2013 and March 31, 2013, is as follows:


	(In thousands, except weighted average data)	September 30,			March 31,
	(In thousands, except weighted average data)	2013			2013
	Aggregate debt outstanding	$	35,000			175,000
	Weighted average remaining life in years		1.8			0.7
	Weighted average coupon rate on notes outstanding		4.61	%		4.47	%
	Fair value of debt outstanding		36,454			178,227

August 2011 Senior Notes	'
Schedule of Aggregate Amount of Senior Unsecured Notes Outstanding	'
	August 2011 Senior Notes
	On August 15, 2011, the company issued $165 million of senior unsecured notes to a group of institutional investors. A summary of these notes outstanding at September 30, 2013 and March 31, 2013, is as follows:


	(In thousands, except weighted average data)	September 30,			March 31,
	(In thousands, except weighted average data)	2013			2013
	Aggregate debt outstanding	$	165,000			165,000
	Weighted average remaining life in years		7.1			7.6
	Weighted average coupon rate on notes outstanding		4.42	%		4.42	%
	Fair value of debt outstanding		169,686			179,802

September 2013 Senior Notes	'
Schedule of Aggregate Amount of Senior Unsecured Notes Outstanding	'
	September 2013 Senior Notes
	On September 30, 2013, the company executed a note purchase agreement for $500 million and issued $300 million of senior unsecured notes to a group of institutional investors. In accordance with the note purchase agreement, the company intends to issue the remaining $200 million of senior unsecured notes on November 15, 2013. A summary of these notes outstanding at September 30, 2013, is as follows:


	(In thousands, except weighted average data)	September 30,
	(In thousands, except weighted average data)	2013
	Aggregate debt outstanding	$	300,000
	Weighted average remaining life in years		9.3
	Weighted average coupon rate on notes outstanding		4.73	%
	Fair value of debt outstanding		307,601

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	6 Months Ended
Earnings Per Share (Tables)	Sep. 30, 2013
Components of Basic and Diluted Earnings Per Share	'
	The components of basic and diluted earnings per share for the quarters and the six-month periods ended September 30, are as follows:


		Quarter Ended				Six Months Ended
		September 30,				September 30,
	(In thousands, except share and per share data)	2013		2012		2013		2012
	Net Income available to common shareholders (A)	$	54,172		41,356		84,255		74,212
	Weighted average outstanding shares of common stock, basic (B)		49,274,816		49,392,973		49,253,409		49,792,212
	Dilutive effect of options and restricted stock awards and units		448,303		232,097		395,983		214,291

	Weighted average common stock and equivalents (C)		49,723,119		49,625,070		49,649,392		50,006,503

	Earnings per share, basic (A/B)	$	1.1		0.84		1.71		1.49
	Earnings per share, diluted (A/C)	$	1.09		0.83		1.7		1.48

	Additional information:
	Antidilutive incremental options and restricted stock awards and units		2,854		54,694		2,854		51,864

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	6 Months Ended
Commitments and Contingencies (Tables)	Sep. 30, 2013
Schedule of Vessel and Remotely Operated Vehicles Commitments	'
	The table below summarizes the company’s various vessel commitments to acquire and construct new vessels, by vessel type, and remotely operated vehicles (ROVs) as of September 30, 2013:


	(In thousands, except vessel count)	Number		Total		Invested		Remaining
		of		Cost		Through		Balance
		Vessels/ROVs				9/30/13		9/30/13
	Vessels under construction:
	Deepwater platform supply vessels		22	$	739,794		233,436		506,358
	Towing supply/supply vessels		6		113,395		46,506		66,889
	Other		2		33,917		28,455		5,462

	Total vessels under construction		30		887,106		308,397		578,709

	Vessels to be purchased:
	Deepwater platform supply vessels		1		46,845		---		46,845

	Total vessel commitments		31	$	933,951		308,397		625,554

	Total ROV commitments		5	$	26,167		7,850		18,317

	Total commitments		36	$	960,118		316,247		643,871

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	6 Months Ended
Fair Value Measurements (Tables)	Sep. 30, 2013
Schedule of Fair Value Assets Measurement	'

	The following table provides the fair value hierarchy for the plan assets measured at fair value as of September 30, 2013:



	(In thousands)	Total			Quoted prices in			Significant		Significant
					active markets			observable		unobservable
					(Level 1)			inputs		inputs
								(Level 2)		(Level 3)
	Equity securities:
	Common stock	$	4,039			4,039			---		---
	Preferred stock		---			---			---		---
	Foreign stock		316			316			---		---
	American depository receipts		1,697			1,697			---		---
	Preferred American depository receipts		13			13			---		---
	Real estate investment trusts		---			---			---		---
	Debt securities:
	Government debt securities		1,786			1,114			672		---
	Open ended mutual funds		1,563			1,563			---		---
	Cash and cash equivalents		1,032			401			631		---

	Total	$	10,446			9,143			1,303		---
	Other pending transactions		(264	)		(264	)		---		---

	Total fair value of plan assets	$	10,182			8,879			1,303		---

	The following table provides the fair value hierarchy for the plan assets measured at fair value as of March 31, 2013:


	(In thousands)	Total			Quoted prices in			Significant		Significant
					active markets			observable		unobservable
					(Level 1)			inputs		inputs
								(Level 2)		(Level 3)
	Equity securities:
	Common stock	$	4,240			4,240			---		---
	Preferred stock		---			---			---		---
	Foreign stock		285			285			---		---
	American depository receipts		1,811			1,811			---		---
	Preferred American depository receipts		16			16			---		---
	Real estate investment trusts		---			---			---		---
	Debt securities:
	Government debt securities		2,007			1,240			767		---
	Open ended mutual funds		1,743			1,743			---		---
	Cash and cash equivalents		533			93			440		---

	Total	$	10,635			9,428			1,207		---
	Other pending transactions		(149	)		(149	)		---		---

	Total fair value of plan assets	$	10,486			9,279			1,207		---

Schedule of Fair Value Other Financial Instruments Measured	'
	The following table provides the fair value hierarchy for the company’s other financial instruments measured as of September 30, 2013:


	(In thousands)	Total			Quoted prices in			Significant		Significant
					active markets			observable		unobservable
					(Level 1)			inputs		inputs
								(Level 2)		(Level 3)
	Cash equivalents	$	376			376			---		---
	Long-term British pound forward derivative contracts		1,132			---			1,132		---

	Total fair value of assets	$	1,508			376			1,132		---


	The following table provides the fair value hierarchy for the company’s other financial instruments measured as of March 31, 2013:


	(In thousands)	Total			Quoted prices in			Significant		Significant
					active markets			observable		unobservable
					(Level 1)			inputs		inputs
								(Level 2)		(Level 3)
	Cash equivalents	$	949			949			---		---
	Long-term British pound forward derivative contracts		4,359			---			4,359		---

	Total fair value of assets	$	5,308			949			4,359		---

Summary of Gain on Assets Disposition	'
	The impairment charges were recorded in gain on asset dispositions, net.


		Quarter Ended						Six Months Ended
		September 30,						September 30,
	(In thousands)	2013			2012			2013		2012
	Amount of impairment incurred	$	175			790			4,047		3,564
	Combined fair value of assets incurring impairment		161			1,192			4,466		8,602

Other_Assets_Accrued_Expenses_1

Other Assets, Accrued Expenses, Other Current Liabilities and Other Liabilities and Deferred Credits (Tables)	6 Months Ended
	Sep. 30, 2013
Schedule of Other Assets	'
	A summary of other assets at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)	September 30,		March 31,
	(In thousands)	2013		2013
	Recoverable insurance losses	$	9,870		10,833
	Deferred income tax assets		82,328		73,105
	Deferred finance charges		8,161		5,133
	Savings plans and supplemental plan		22,026		23,149
	Noncurrent tax receivable		9,106		9,106
	Other		17,748		4,951

		$	149,239		126,277

Schedule of Accrued Expenses	'
	A summary of accrued expenses at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)	September 30,		March 31,
	(In thousands)	2013		2013
	Payroll and related payables	$	21,747		23,453
	Commissions payable		31,378		13,866
	Accrued vessel expenses		103,098		103,177
	Accrued interest expense		5,443		8,096
	Other accrued expenses		6,519		10,494

		$	168,185		159,086

Schedule of Other Current Liabilities	'
	A summary of other current liabilities at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)	September 30,		March 31,
	(In thousands)	2013		2013
	Taxes payable	$	38,205		38,100
	Deferred credits - current		649		1,374
	Dividend payable		480		334

		$	39,334		39,808

Schedule of Other Liabilities and Deferred Credits	'
	A summary of other liabilities and deferred credits at September 30, 2013 and March 31, 2013 is as follows:


	(In thousands)	September 30,		March 31,
	(In thousands)	2013		2013
	Postretirement benefits liability	$	26,939		27,681
	Pension liabilities		39,332		37,096
	Deferred gain on vessel sales		71,544		39,568
	Other		36,555		34,729

		$	174,370		139,074

Segment_and_Geographic_Distrib1

Segment and Geographic Distribution of Operations (Tables)	6 Months Ended
Segment and Geographic Distribution of Operations (Tables)	Sep. 30, 2013
Segment Information, Geographical Data and Major Customers	'
	The following table provides a comparison of revenues, vessel operating profit, depreciation and amortization, and additions to properties and equipment for the quarters and six-month periods ended September 30, 2013 and 2012. Vessel revenues and operating costs relate to vessels owned and operated by the company while other operating revenues relate to the activities of the company’s shipyards, brokered vessels and other miscellaneous marine-related businesses.


			Quarter Ended						Six Months Ended
			September 30,						September 30,
	(In thousands)		2013			2012			2013			2012
	Revenues:
	Vessel revenues:
	Americas		$	101,929			82,316			192,173			159,966
	Asia/Pacific			37,430			45,738			80,386			97,480
	Middle East/N. Africa			45,370			32,051			86,583			64,501
	Sub-Saharan Africa/Europe			178,939			149,717			336,156			277,969

				363,668			309,822			695,298			599,916
	Other operating revenues			4,269			2,096			6,724			6,450

			$	367,937			311,918			702,022			606,366

	Vessel operating profit:
	Americas		$	23,675			9,506			43,976			19,698
	Asia/Pacific			4,807			7,826			15,096			22,734
	Middle East/N. Africa			13,446			6,280			23,569			12,562
	Sub-Saharan Africa/Europe			47,261			44,330			64,780			71,426

				89,189			67,942			147,421			126,420
	Corporate expenses			(12,891	)		(12,484	)		(29,446	)		(22,951	)
	Gain on asset dispositions, net			49			1,833			2,189			2,671
	Other operating expense			218			(94	)		(174	)		544

	Operating income		$	76,565			57,197			119,990			106,684

	Foreign exchange gain (loss)			3,017			529			2,928			(1,222	)
	Equity in net earnings of unconsolidated companies			3,781			3,357			8,201			5,720
	Interest income and other, net			538			1,128			1,278			1,847
	Loss on early extinguishment of debt			(4,144	)		---			(4,144	)		---
	Interest and other debt costs			(9,918	)		(7,148	)		(18,831	)		(14,735	)

	Earnings before income taxes		$	69,839			55,063			109,422			98,294

	Depreciation and amortization:
	Americas		$	10,833			10,629			20,945			20,721
	Asia/Pacific			4,122			4,833			8,647			9,946
	Middle East/N. Africa			5,731			4,388			11,337			8,467
	Sub-Saharan Africa/Europe			20,581			15,309			39,736			30,802
	Corporate			789			888			1,499			1,895

			$	42,056			36,047			82,164			71,831

	Additions to properties and equipment:
	Americas		$	8,845			25,118			12,039			41,896
	Asia/Pacific			453			5,071			968			5,165
	Middle East/N. Africa			770			721			909			1,795
	Sub-Saharan Africa/Europe (A)			8,086			36,659			344,557			48,534
	Corporate (B)			49,747			44,194			111,597			88,285

			$	67,901			111,763			470,070			185,675


	(A)	Included in Sub-Saharan Africa/Europe for the six months ended September 30, 2013 is $245.6 million related to vessels acquired through the acquisition of Troms Offshore.

	(B)	Included in Corporate are additions to properties and equipment relating to vessels currently under construction which have not yet been assigned to a non-corporate reporting segment as of the dates presented.


Comparison of Total Assets	'
	The following table provides a comparison of total assets at September 30, 2013 and March 31, 2013:


	(In thousands)		September 30,			March 31,
	(In thousands)		2013			2013
	Total assets:
	Americas		$	930,475			885,470
	Asia/Pacific			487,850			607,546
	Middle East/North Africa			584,805			507,124
	Sub-Saharan Africa/Europe			2,214,683			1,706,355

				4,217,813			3,706,495
	Investments in, at equity, and advances to unconsolidated companies			52,254			46,047

				4,270,067			3,752,542
	Corporate (A)			484,512			415,513

			$	4,754,579			4,168,055

	Note A: Included in Corporate are vessels currently under construction which have not yet been assigned to a non-corporate reporting segment. The vessel construction costs will be reported in Corporate until the earlier of the vessels being assigned to a non-corporate reporting segment or the vessels’ delivery. At September 30, 2013 and March 31, 2013, $306.7 million and $229.3 million, respectively, of vessel construction costs are included in Corporate.
Schedule of Segment Reporting Information, Revenue by Vessel Class	'
	The following table discloses the amount of revenue by segment, and in total for the worldwide fleet, along with the respective percentage of total vessel revenue for the quarters and six-month periods ended September 30, 2013 and 2012:


	Revenue by vessel class		Quarter Ended September 30,												Six Months Ended September 30,
	(In thousands)		2013			%			2012			%			2013		%		2012		%
	Americas fleet:
	Deepwater vessels		$	61,811			17%			44,747			14%			116,843		17%		81,027		14%
	Towing-supply/supply			30,861			8%			31,109			10%			58,531		8%		65,461		11%
	Other			9,257			3%			6,460			2%			16,799		3%		13,478		2%
	Total		$	101,929			28%			82,316			27%			192,173		28%		159,966		27%
	Asia/Pacific fleet:
	Deepwater vessels		$	19,923			5%			24,592			8%			44,215		6%		49,929		8%
	Towing-supply/supply			16,559			5%			20,229			7%			34,281		5%		45,729		8%
	Other			948			<1%			917			<1%			1,890		<1%		1,822		<1%
	Total		$	37,430			10%			45,738			15%			80,386		11%		97,480		16%
	Middle East/N. Africa fleet:
	Deepwater vessels		$	15,732			5%			12,275			4%			31,584		5%		23,559		4%
	Towing-supply/supply			28,763			8%			18,859			6%			53,260		8%		38,859		6%
	Other			875			<1%			917			<1%			1,739		<1%		2,083		<1%
	Total		$	45,370			13%			32,051			10%			86,583		13%		64,501		10%
	Sub-Saharan Africa/Europe fleet:
	Deepwater vessels		$	106,541			29%			67,696			22%			193,792		28%		130,311		22%
	Towing-supply/supply			56,772			16%			63,548			20%			111,632		16%		112,560		20%
	Other			15,626			4%			18,473			6%			30,732		4%		35,098		6%
	Total		$	178,939			49%			149,717			48%			336,156		48%		277,969		47%
	Worldwide fleet:
	Deepwater vessels		$	204,007			56%			149,310			48%			386,434		56%		284,826		47%
	Towing-supply/supply			132,955			37%			133,745			43%			257,704		37%		262,609		44%
	Other			26,706			7%			26,767			9%			51,160		7%		52,481		9%
	Total		$	363,668			100%			309,822			100%			695,298		100%		599,916		100%

Goodwill_Tables

Goodwill (Tables)	6 Months Ended
Goodwill (Tables)	Sep. 30, 2013
Schedule of Goodwill by Reportable Segment	'
	Goodwill by reportable segment at September 30, 2013 and at March 31, 2013 is as follows:


	(In thousands)	September 30,		March 31,
	(In thousands)	2013		2013
	Americas	$	114,237		114,237
	Asia/Pacific		56,283		56,283
	Sub-Saharan Africa/Europe		169,462		127,302

		$	339,982		297,822

SaleLeaseback_Arrangements_Tab

Sale/Leaseback Arrangements (Tables)	6 Months Ended
Sale/Leaseback Arrangements (Tables)	Sep. 30, 2013
Schedule of Future Minimum Lease Payments	'
	As of September 30, 2013, the future minimum lease payments for these two vessels under the operating lease terms are as follows:


	Fiscal year ending	Amount
	Fiscal year ending	(In thousands)
	Remaining six-months of 2014	$	2,794
	2015		5,588
	2016		5,589
	2017		5,589
	2018		6,830
	Thereafter		17,076

	Total future lease payments	$	43,466

Acquisition_Additional_Informa

Acquisition - Additional Information (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013	Jun. 04, 2013
Acquisition - Additional Information (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013	Troms Offshore Supply AS
Business Acquisition [Line Items]	'	'	'
Business acquisition, description of acquired entity	'	'	'Troms Offshore owned four deepwater PSVs, and had two additional deepwater PSVs under construction, one of which was delivered shortly after the acquisition.
Business acquisition, cash paid	'	'	$150,000,000
Business acquisition, debt assumed	'	'	261,300,000
Business acquisition, Goodwill	$339,982,000	$297,822,000	$42,160,000

Allocation_of_Purchase_Price_f

Allocation of Purchase Price for Acquisition (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013	Jun. 04, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013	Troms Offshore Supply AS
Business Combination Allocation of Purchase Price [Line Items]	'	'	'
Cash	'	'	$22,263
Trade receivables and other current assets	'	'	9,816
Vessels	'	'	245,605
Goodwill	339,982	297,822	42,160
Payable and other liabilities	'	'	-13,020
Notes payable	'	'	-156,824
Total purchase price	'	'	$150,000

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	1 Months Ended
In Millions, unless otherwise specified	15-May-13	17-May-12
	May 2013 Authorized Amount	May 2012 Authorized Amount
Stockholders Equity Note [Line Items]	'	'
Amount authorized to repurchase shares	$200	$200

Schedule_of_Common_Stock_Repur

Schedule of Common Stock Repurchased and Average Price Paid Per Share (Detail) (USD $)	6 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2012
Stockholders' Equity [Abstract]	'
Aggregate dollar outlay for common stock repurchased	$65,028
Shares of common stock repurchased	1,400,500
Average price paid per common share	$46.43

Schedule_of_Dividends_Declared

Schedule of Dividends Declared (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Stockholders' Equity [Abstract]	'	'	'	'
Dividends declared	$12,536	$12,544	$25,035	$25,169
Dividend per share	$0.25	$0.25	$0.50	$0.50

Changes_in_Accumulated_Other_C

Changes in Accumulated Other Comprehensive Income by Component, Net of Tax (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Other comprehensive income before reclassifications, Beginning Balance	($16,913)	($19,838)	($17,141)	($19,330)
Gains/(Losses) recognized in other comprehensive income	-237	410	-206	-351
Amounts reclassified from accumulated other comprehensive income to net income:	180	126	377	379
Net current period other comprehensive income	-57	536	171	28
Other comprehensive income before reclassifications, Ending Balance	-16,970	-19,302	-16,970	-19,302
Available-for-sale Securities	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Other comprehensive income before reclassifications, Beginning Balance	-10	-373	-121	251
Gains/(Losses) recognized in other comprehensive income	-237	410	-206	-351
Amounts reclassified from accumulated other comprehensive income to net income:	64	9	144	146
Net current period other comprehensive income	-173	419	-62	-205
Other comprehensive income before reclassifications, Ending Balance	-183	46	-183	46
Currency Translation Adjustments	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Other comprehensive income before reclassifications, Beginning Balance	-9,811	-9,811	-9,811	-9,811
Gains/(Losses) recognized in other comprehensive income	'	'	'	'
Amounts reclassified from accumulated other comprehensive income to net income:	'	'	'	'
Net current period other comprehensive income	'	'	'	'
Other comprehensive income before reclassifications, Ending Balance	-9,811	-9,811	-9,811	-9,811
Pensions /Post Retirement Benefits	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Other comprehensive income before reclassifications, Beginning Balance	-4,353	-6,448	-4,353	-6,448
Gains/(Losses) recognized in other comprehensive income	'	'	'	'
Amounts reclassified from accumulated other comprehensive income to net income:	'	'	'	'
Net current period other comprehensive income	'	'	'	'
Other comprehensive income before reclassifications, Ending Balance	-4,353	-6,448	-4,353	-6,448
Interest Rate Swaps	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Other comprehensive income before reclassifications, Beginning Balance	-2,739	-3,206	-2,856	-3,322
Gains/(Losses) recognized in other comprehensive income	'	'	'	'
Amounts reclassified from accumulated other comprehensive income to net income:	116	117	233	233
Net current period other comprehensive income	116	117	233	233
Other comprehensive income before reclassifications, Ending Balance	($2,623)	($3,089)	($2,623)	($3,089)

Reclassifications_from_Accumul

Reclassifications from Accumulated Other Comprehensive Loss to Condensed Consolidated Statement of Income (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Total pre-tax amounts	$277	$195	$580	$583
Tax effect	97	68	203	204
Total gains for the period, net of tax	180	127	377	379
Interest income and other, net	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Realized gains on available for-sale securities	99	15	222	225
Interest and other debt costs	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Amortization of interest rate swap	$178	$180	$358	$358

Schedule_of_Effective_Tax_Rate

Schedule of Effective Tax Rate Applicable to Pre-Tax Earnings (Detail)	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule of Effective Tax Rate Reconciliation [Line Items]	'	'	'	'
Effective tax rate applicable to pre-tax earnings	22.40%	24.90%	23.00%	24.50%

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail)	6 Months Ended
Income Taxes - Additional Information (Detail)	Sep. 30, 2013	Sep. 30, 2012
Income Tax [Line Items]	'	'
Federal statutory tax rate	35.00%	35.00%

Schedule_of_Uncertain_Tax_Posi

Schedule of Uncertain Tax Positions and Income Tax Payable (Detail) (USD $)	Sep. 30, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013
Income Tax [Line Items]	'
Tax liabilities for uncertain tax positions	$16,304
Income tax payable	$32,787

Schedule_of_Unrecognized_Tax_B

Schedule of Unrecognized Tax Benefits Which Would Lower Effective Tax Rate if Realized (Detail) (State and Local Jurisdiction, USD $)	6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
State and Local Jurisdiction	'
Income Tax Contingency [Line Items]	'
Unrecognized tax benefit related to state tax issues	$8,202
Interest receivable on unrecognized tax benefit related to state tax issues	$20

Employee_Benefit_Plans_Additio

Employee Benefit Plans - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
U.S. Defined Benefit Pension Plan	'	'	'	'
Defined Contribution and Defined Benefit Plans [Line Items]	'	'	'	'
Defined benefit plan, employer contributions	$0	$0	$0	$0
Expected employer contributions to the plan during the remaining quarters of the fiscal period	0	'	0	'
Supplemental Executive Retirement Plan	'	'	'	'
Defined Contribution and Defined Benefit Plans [Line Items]	'	'	'	'
Defined benefit plan, employer contributions	0	0	0	0
Expected employer contributions to the plan during the remaining quarters of the fiscal period	$0	'	$0	'

Schedule_of_Carrying_Value_of_

Schedule of Carrying Value of Trust Assets, Including Unrealized Gains or Losses (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Defined Benefit Plan Disclosure [Line Items]	'	'
Investments held in Rabbi Trust	$10,182	$10,486
Unrealized gains (losses) in fair value of trust assets	-183	-121
Unrealized gains (losses) in fair value of trust assets are net of income tax expense of	-98	-65
Obligations under the supplemental plan	$22,260	$21,431

Schedule_of_Net_Periodic_Benef

Schedule of Net Periodic Benefit Cost (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Pension Plan and Supplemental Plan	'	'	'	'
Net Period Benefit Cost Assumptions [Line Items]	'	'	'	'
Service cost	$198	$273	$396	$546
Interest cost	895	1,072	1,790	2,144
Expected return on plan assets	-718	-687	-1,436	-1,374
Amortization of prior service cost	12	12	24	24
Recognized actuarial (gain) loss	276	448	552	896
Net periodic benefit cost	663	1,118	1,326	2,236
Other Benefits	'	'	'	'
Net Period Benefit Cost Assumptions [Line Items]	'	'	'	'
Service cost	101	119	202	238
Interest cost	262	309	524	618
Amortization of prior service cost	-508	-508	-1,016	-1,016
Recognized actuarial (gain) loss	-99	'	-198	'
Net periodic benefit cost	($244)	($80)	($488)	($160)

Indebtedness_Revolving_Credit_

Indebtedness - Revolving Credit and Term Loan Agreement - Additional Information (Detail) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Mar. 31, 2013
	Minimum	Maximum	Current Credit Facility	Prime or Federal Funds	Prime or Federal Funds	Eurodollar Rates	Eurodollar Rates	Term Loan Facility	Term Loan Facility	Revolving Credit Agreement	Revolving Credit Agreement
				Minimum	Maximum	Minimum	Maximum
Debt [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Credit facility expiration date	'	'	'2018-06	'	'	'	'	'	'	'	'
Revolving credit facility	'	'	$900	'	'	'	'	'	'	'	'
Credit facility term	'	'	'5 years	'	'	'	'	'	'	'	'
Revolving line of credit	'	'	600	'	'	'	'	'	'	'	'
Term loan	'	'	300	'	'	'	'	'	'	'	'
Revolving credit rate	'	'	'	0.25%	1.00%	1.25%	2.00%	'	'	'	'
Consolidated debt to consolidated total capitalization, ratio	'	55.00%	'	'	'	'	'	'	'	'	'
Interest coverage ratio	300.00%	'	'	'	'	'	'	'	'	'	'
Commitment fees on the unused portion of credit facility	0.15%	0.30%	'	'	'	'	'	'	'	'	'
Outstanding borrowing	'	'	'	'	'	'	'	300	'	180	110
Revolving credit facility, remaining borrowing capacity	'	'	420	'	'	'	'	'	'	'	'
Term loan facility, current borrowing capacity	'	'	'	'	'	'	'	'	$125	'	'

Indebtedness_Senior_Debt_Notes

Indebtedness - Senior Debt Notes - Additional Information (Detail)

3 Months Ended

6 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

1 Months Ended

6 Months Ended

1 Months Ended

6 Months Ended

12 Months Ended

6 Months Ended

12 Months Ended

6 Months Ended

1 Months Ended

6 Months Ended

12 Months Ended

6 Months Ended

1 Months Ended

6 Months Ended

1 Months Ended

6 Months Ended

1 Months Ended

Sep. 30, 2013

Jun. 30, 2013

Sep. 30, 2013

31-May-12

Sep. 30, 2013

31-May-12

Jun. 30, 2013

Sep. 30, 2013

31-May-12

Jun. 30, 2013

Sep. 30, 2013

31-May-12

Jun. 30, 2013

Aug. 15, 2011

Sep. 30, 2013

Mar. 31, 2013

Sep. 30, 2013

Mar. 31, 2013

Mar. 31, 2011

Sep. 30, 2013

Jul. 31, 2003

Sep. 30, 2013

Mar. 31, 2013

Sep. 30, 2013

Nov. 15, 2013

Sep. 30, 2013

Nov. 15, 2013

Sep. 30, 2013

Nov. 15, 2013

USD ($)

Troms Offshore Supply AS

Minimum

Maximum

August 2011 Senior Unsecured Notes

September 2010 Senior Unsecured Notes

July 2003 Senior Unsecured Notes

September 2013 Senior Unsecured Notes

USD ($)

NOK

USD ($)

NOK

Notes Due May 2024

Public bonds

Notes Due May 2015

Senior Notes Due 2019

Floating rate debt

Fixed rate debt

Troms Offshore Supply AS

USD ($)

Minimum

Maximum

USD ($)

Minimum

Maximum

USD ($)

Minimum

Maximum

USD ($)

Subsequent Event

Minimum

Maximum

NOK

USD ($)

NOK

USD ($)

NOK

USD ($)

NOK

USD ($)

NOK

Public bonds

Notes Due May 2015

Senior Notes Due 2019

Notes Due May 2015

Senior Notes Due 2019

USD ($)

Subsequent Event

Debt [Line Items]

Senior note issuable amount under purchase agreement

$500,000,000

Sale of debt outstanding

165,000,000

425,000,000

300,000,000

200,000,000

Debt instrument maturity, in years

'8 years

'10 years

'5 years

'12 years

'7 years

'12 years

'7 years

'10 years

'12 years

Weighted average remaining life in years

7.1

7.6

6.1

6.6

1.8

0.7

9.3

10.8

Weighted average coupon rate on notes outstanding

4.42%

4.25%

4.61%

4.47%

4.73%

5.06%

Consolidated debt to consolidated total capitalization, ratio

55.00%

Interest coverage ratio

300.00%

After-tax loss relating to interest rate hedges

2,600,000

2,900,000

Pre-tax loss relating to interest rate hedges

4,000,000

4,400,000

Debt extinguished amount

32,500,000

188,900,000

82,100,000

500,000,000

Repayment of bond at average price as a percentage of par value

105.00%

Loss on early extinguishment of bond

-4,144,000

4,100,000

26,000,000

Maturity date

'2016-04

Interest rate

5.40%

2.00%

3.50%

Debt instruments face amount

204,400,000

35,000,000

25,000,000

Debt instrument maturity, month and year

'2024-05

'2015-05

'2019-06

Semi-annual principal payments

8,500,000

Debt instrument bearing interest rate

6.38%

Debt instrument outstanding amount

9,900,000

60,000,000

30,800,000

187,400,000

9,900,000

60,000,000

30,800,000

187,400,000

Debt instrument estimated fair value

32,300,000

196,600,000

Principal repayments due on long term debt

$5,300,000

Credit facility maturity year and month

'2018-06

Schedule_of_Aggregate_Amount_o

Schedule of Aggregate Amount of Senior Unsecured Notes Outstanding (Detail) (USD $)	6 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
	Y	Y
September 2013 Senior Unsecured Notes	'	'
Debt [Line Items]	'	'
Aggregate debt outstanding	$300,000	'
Weighted average remaining life in years	9.3	'
Weighted average coupon rate on notes outstanding	4.73%	'
Fair value of debt outstanding	307,601	'
August 2011 Senior Unsecured Notes	'	'
Debt [Line Items]	'	'
Aggregate debt outstanding	165,000	165,000
Weighted average remaining life in years	7.1	7.6
Weighted average coupon rate on notes outstanding	4.42%	4.42%
Fair value of debt outstanding	169,686	179,802
September 2010 Senior Unsecured Notes	'	'
Debt [Line Items]	'	'
Aggregate debt outstanding	425,000	425,000
Weighted average remaining life in years	6.1	6.6
Weighted average coupon rate on notes outstanding	4.25%	4.25%
Fair value of debt outstanding	436,530	458,520
July 2003 Senior Unsecured Notes	'	'
Debt [Line Items]	'	'
Aggregate debt outstanding	35,000	175,000
Weighted average remaining life in years	1.8	0.7
Weighted average coupon rate on notes outstanding	4.61%	4.47%
Fair value of debt outstanding	$36,454	$178,227

Debt_Costs_Detail

Debt Costs (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Debt [Line Items]	'	'	'	'
Interest and debt costs incurred, net of interest capitalized	$9,918	$7,148	$18,831	$14,735
Interest costs capitalized	2,636	2,913	5,598	5,736
Total interest and debt costs	$12,554	$10,061	$24,429	$20,471

Components_of_Basic_and_Dilute

Components of Basic and Diluted Earnings Per Share (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule Of Earnings Per Share Basic And Diluted [Line Items]	'	'	'	'
Net Income available to common shareholders (A)	$54,172	$41,356	$84,255	$74,212
Weighted average outstanding shares of common stock, basic (B)	49,274,816	49,392,973	49,253,409	49,792,212
Dilutive effect of options and restricted stock awards and units	448,303	232,097	395,983	214,291
Weighted average common stock and equivalents (C)	49,723,119	49,625,070	49,649,392	50,006,503
Earnings per share, basic (A/B)	$1.10	$0.84	$1.71	$1.49
Earnings per share, diluted (A/C)	$1.09	$0.83	$1.70	$1.48
Antidilutive incremental options and restricted stock awards and units	2,854	54,694	2,854	51,864

Schedule_of_Vessel_and_Remotel

Schedule of Vessel and Remotely Operated Vehicles Commitments (Detail) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
	Vessel
Significant Purchase and Supply Commitment [Line Items]	'
Number of vessels/ROVs under construction	30
Total cost, under construction	$887,106
Invested, under construction	308,397
Remaining Balance, under construction	578,709
Invested, to be purchased	'
Number of Vessels/ROVs, commitments	36
Total cost, commitments	960,118
Invested, commitments	316,247
Remaining Balance, commitments	643,871
Vessel Commitments	'
Significant Purchase and Supply Commitment [Line Items]	'
Number of Vessels/ROVs, commitments	31
Total cost, commitments	933,951
Invested, commitments	308,397
Remaining Balance, commitments	625,554
Remotely Operated Vehicles Commitments	'
Significant Purchase and Supply Commitment [Line Items]	'
Number of Vessels/ROVs, commitments	5
Total cost, commitments	26,167
Invested, commitments	7,850
Remaining Balance, commitments	18,317
Deepwater Platform Supply Vessels	'
Significant Purchase and Supply Commitment [Line Items]	'
Number of vessels/ROVs under construction	22
Total cost, under construction	739,794
Invested, under construction	233,436
Remaining Balance, under construction	506,358
Number of Vessels/ROVs to be purchased	1
Total cost, to be purchased	46,845
Invested, to be purchased	'
Remaining Balance, to be purchased	46,845
Towing-Supply/Supply Vessels	'
Significant Purchase and Supply Commitment [Line Items]	'
Number of vessels/ROVs under construction	6
Total cost, under construction	113,395
Invested, under construction	46,506
Remaining Balance, under construction	66,889
Other	'
Significant Purchase and Supply Commitment [Line Items]	'
Number of vessels/ROVs under construction	2
Total cost, under construction	33,917
Invested, under construction	28,455
Remaining Balance, under construction	$5,462

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	6 Months Ended				1 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Oct. 31, 2013
	Vessel	Fast, Crew/Supply Boat	Towing-Supply/Supply Vessels	Deepwater Platform Supply Vessels	Deepwater Platform Supply Vessels
		Vessel	Vessel	Vessel	Subsequent Event
				T	Vessel
Significant Purchase and Supply Commitment [Line Items]	'	'	'	'	'
Significant commitment, new construction brake horsepower	'	'	7,100	'	'
Significant commitment, new construction deadweight tons capacity range, low	'	'	'	3,000	'
Significant commitment, new construction deadweight tons capacity range, high	'	'	'	6,360	'
Significant commitment, new construction final delivery date	'February 2016	'	'	'	'
Number of vessels under construction	30	1	6	22	'
Insurance coverage for the progress payments made on the vessel by the third party credit support	'	90.00%	'	'	'
Insurance coverage by the third party credit support for the carrying value of the accumulated costs	'	$2.40	'	'	'
Committed and invested amount	'	8	'	'	'
Number of vessals took for delivery	'	'	'	'	1
Amount held as escrow	'	'	'	'	7.8
Deferred prosecution agreement fine	7.35	'	'	'	'
Contingent civil penalty eliminated due to settlement	$3	'	'	'	'

Commitments_and_Contingencies_2

Commitments and Contingencies (Merchant Navy Officers Pension Fund) - Additional Information (Detail) (Merchant Navy Officers Pension Fund)	1 Months Ended
	Jul. 15, 2013
	Vessel
Merchant Navy Officers Pension Fund	'
Commitments and Contingencies Disclosure [Line Items]	'
Number of Vessels to be purchased	7

Commitments_and_Contingencies_3

Commitments and Contingencies (Sonatide Joint Venture) - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2013
Commitments and Contingencies Disclosure [Line Items]	'	'	'	'	'
Vessel revenues	$363,668,000	$309,822,000	$695,298,000	$599,916,000	'
Investments in, at equity, and advances to unconsolidated companies	52,254,000	'	52,254,000	'	46,047,000
Commissions payable	31,378,000	'	31,378,000	'	13,866,000
Sonatide joint venture	'	'	'	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'	'	'	'
Number of contracts	'	'	6	'	'
Number of vessels operating	10	'	10	'	'
Ownership Interest In Joint Venture	49.00%	'	49.00%	'	'
Investments in, at equity, and advances to unconsolidated companies	53,000,000	'	53,000,000	'	46,000,000
Sonatide joint venture \| Trade and other receivables	'	'	'	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'	'	'	'
Due to related parties	280,000,000	'	280,000,000	'	'
Sonatide joint venture \| Accrued expenses	'	'	'	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'	'	'	'
Due to related parties	70,000,000	'	70,000,000	'	'
Commissions payable	24,000,000	'	24,000,000	'	'
Sonatide joint venture \| ANGOLA	'	'	'	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'	'	'	'
Vessel revenues	'	'	$167,700,000	$134,300,000	'
Percentage of Angolan operation revenue	'	'	24.00%	22.00%	'
Number of vessels operating	89	86	89	86	'
Number of vessels stacked	6	11	6	11	'

Commitments_and_Contingencies_4

Commitments and Contingencies (Brazilian Customs) - Additional Information (Detail)	1 Months Ended	6 Months Ended
In Millions, unless otherwise specified	Apr. 30, 2011	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013
	BRL	USD ($)	BRL	Revised	Revised
	Vessel			USD ($)	BRL
Commitments and Contingencies Disclosure [Line Items]	'	'	'	'	'
Fines assessed	155	$68.60	'	$56.20	127
Number of Tidewater vessels that the subsidiaries failed to obtain import licenses from	17	'	'	'	'
Disallowed amount of total fines by the administrative appeals board	'	65.9	149	'	'
Remaining amount of fines contested	'	12.4	28	'	'
Decision disallowing the fines totaling	'	'	127	'	'

Commitments_and_Contingencies_5

Commitments and Contingencies (Potential for Future Brazilian State Tax Assessment) - Additional Information (Detail)	6 Months Ended
	Sep. 30, 2013
	Y
Commitments and Contingencies Disclosure [Line Items]	'
Number of competitors notified	2
Statute of limitations, years	5
Maximum, Prior To December 31, 2010	'
Commitments and Contingencies Disclosure [Line Items]	'
Import tax, percentage	16.00%
Maximum, After December 31, 2010	'
Commitments and Contingencies Disclosure [Line Items]	'
Import tax, percentage	3.00%

Commitment_and_Contingencies_N

Commitment and Contingencies (Nigeria Marketing Agent Litigation) - Additional Information (Detail) (Federal Government of Nigeria, USD $)	Mar. 01, 2013
In Millions, unless otherwise specified	Mar. 01, 2013
Federal Government of Nigeria	'
Commitments and Contingencies Disclosure [Line Items]	'
Due to affiliates	$19

Commitments_and_Contingencies_6

Commitments and Contingencies (Venezuelan Operations) - Additional Information (Detail) (USD $)	3 Months Ended	1 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2009	31-May-09	Jul. 31, 2009
		Venezuelan National Oil Company	Petrosucre S
		Vessel	Vessel
Commitments and Contingencies Disclosure [Line Items]	'	'	'
Number of vessels seized	'	11	4
Provision for uncollectible accounts	$44.80	'	'

Schedule_of_Fair_Value_Assets_

Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	$10,446	$10,635
Other pending transactions	-264	-149
Total fair value of plan assets	10,182	10,486
Equity Securities Common Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	4,039	4,240
Foreign Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	316	285
American Depository Receipts	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,697	1,811
Preferred American Depository Receipts	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	13	16
US Treasury and Government	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,786	2,007
Open Ended Mutual Funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,563	1,743
Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,032	533
Quoted Prices In Active Markets (Level 1)	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	9,143	9,428
Other pending transactions	-264	-149
Total fair value of plan assets	8,879	9,279
Quoted Prices In Active Markets (Level 1) \| Equity Securities Common Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	4,039	4,240
Quoted Prices In Active Markets (Level 1) \| Foreign Stock	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	316	285
Quoted Prices In Active Markets (Level 1) \| American Depository Receipts	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,697	1,811
Quoted Prices In Active Markets (Level 1) \| Preferred American Depository Receipts	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	13	16
Quoted Prices In Active Markets (Level 1) \| US Treasury and Government	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,114	1,240
Quoted Prices In Active Markets (Level 1) \| Open Ended Mutual Funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,563	1,743
Quoted Prices In Active Markets (Level 1) \| Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	401	93
Significant Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	1,303	1,207
Total fair value of plan assets	1,303	1,207
Significant Observable Inputs (Level 2) \| US Treasury and Government	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	672	767
Significant Observable Inputs (Level 2) \| Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Fair value of plan assets	$631	$440

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail)	6 Months Ended
	Sep. 30, 2013	Mar. 31, 2013
	D	Contract
	Contract
Derivatives, Fair Value [Line Items]	'	'
Cash equivalents maturity period, days	90	'
Number of contracts outstanding	0	0
British Pound Forward Contracts	'	'
Derivatives, Fair Value [Line Items]	'	'
Number of contracts outstanding	1	3
Expiration dates	'December 18, 2013	'December 18, 2013

Schedule_of_Fair_Value_Other_F

Schedule of Fair Value Other Financial Instruments Measured (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash equivalents	$376	$949
Long-term British pound forward derivative contracts	1,132	4,359
Total fair value of assets	1,508	5,308
Quoted Prices In Active Markets (Level 1)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash equivalents	376	949
Total fair value of assets	376	949
Significant Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term British pound forward derivative contracts	1,132	4,359
Total fair value of assets	$1,132	$4,359

Summary_of_Gain_on_Assets_Disp

Summary of Gain on Assets Disposition (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Fair Value Measurements [Line Items]	'	'	'	'
Amount of impairment incurred	$175	$790	$4,047	$3,564
Combined fair value of assets incurring impairment	$161	$1,192	$4,466	$8,602

Schedule_of_Other_Assets_Detai

Schedule of Other Assets (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Other Assets, Accrued Expenses, Other Current Liabilities, And Other Liabilities And Deferred Credits [Abstract]	'	'
Recoverable insurance losses	$9,870	$10,833
Deferred income tax assets	82,328	73,105
Deferred finance charges	8,161	5,133
Savings plans and supplemental plan	22,026	23,149
Noncurrent tax receivable	9,106	9,106
Other	17,748	4,951
Total other assets	$149,239	$126,277

Schedule_of_Accrued_Expenses_D

Schedule of Accrued Expenses (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Other Assets, Accrued Expenses, Other Current Liabilities, And Other Liabilities And Deferred Credits [Abstract]	'	'
Payroll and related payables	$21,747	$23,453
Commissions payable	31,378	13,866
Accrued vessel expenses	103,098	103,177
Accrued interest expense	5,443	8,096
Other accrued expenses	6,519	10,494
Accrued expenses	$168,185	$159,086

Schedule_of_Other_Current_Liab

Schedule of Other Current Liabilities (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Other Assets, Accrued Expenses, Other Current Liabilities, And Other Liabilities And Deferred Credits [Abstract]	'	'
Taxes payable	$38,205	$38,100
Deferred credits - current	649	1,374
Dividend payable	480	334
Other current liabilities	$39,334	$39,808

Schedule_of_Other_Liabilities_

Schedule of Other Liabilities and Deferred Credits (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Other Assets, Accrued Expenses, Other Current Liabilities, And Other Liabilities And Deferred Credits [Abstract]	'	'
Postretirement benefits liability	$26,939	$27,681
Pension liabilities	39,332	37,096
Deferred gain on vessel sales	71,544	39,568
Other	36,555	34,729
Other liabilities and deferred credits	$174,370	$139,074

Segment_and_Geographic_Distrib2

Segment and Geographic Distribution of Operations - Additional Information (Detail)	6 Months Ended
	Sep. 30, 2013
	Segment
Segment Reporting Information [Line Items]	'
Number of operating segments	4

Segment_Information_Geographic

Segment Information, Geographical Data and Major Customers (Detail) (USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Segment Reporting Information [Line Items]	'		'		'		'
Vessel revenues	$363,668		$309,822		$695,298		$599,916
Other operating revenues	4,269		2,096		6,724		6,450
Total revenues	367,937		311,918		702,022		606,366
Vessel operating profit	89,189		67,942		147,421		126,420
Corporate expenses	-12,891		-12,484		-29,446		-22,951
Depreciation and amortization	42,056		36,047		82,164		71,831
Gain on asset dispositions, net	49		1,833		2,189		2,671
Additions to properties and equipment	'		'		220,309		189,826
Other operating expense	218		-94		-174		544
Operating income	76,565		57,197		119,990		106,684
Foreign exchange gain (loss)	3,017		529		2,928		-1,222
Equity in net earnings of unconsolidated companies	3,781		3,357		8,201		5,720
Interest income and other, net	538		1,128		1,278		1,847
Loss on early extinguishment of debt	-4,144		'		-4,144		'
Interest and other debt costs	-9,918		-7,148		-18,831		-14,735
Earnings before income taxes	69,839		55,063		109,422		98,294
Additions to properties and equipment	67,901		111,763		470,070		185,675
Americas	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Vessel revenues	101,929		82,316		192,173		159,966
Vessel operating profit	23,675		9,506		43,976		19,698
Depreciation and amortization	10,833		10,629		20,945		20,721
Additions to properties and equipment	8,845		25,118		12,039		41,896
Asia/Pacific	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Vessel revenues	37,430		45,738		80,386		97,480
Vessel operating profit	4,807		7,826		15,096		22,734
Depreciation and amortization	4,122		4,833		8,647		9,946
Additions to properties and equipment	453		5,071		968		5,165
Middle East/N. Africa	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Vessel revenues	45,370		32,051		86,583		64,501
Vessel operating profit	13,446		6,280		23,569		12,562
Depreciation and amortization	5,731		4,388		11,337		8,467
Additions to properties and equipment	770		721		909		1,795
Sub-Saharan Africa/Europe	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Vessel revenues	178,939		149,717		336,156		277,969
Vessel operating profit	47,261		44,330		64,780		71,426
Depreciation and amortization	20,581		15,309		39,736		30,802
Additions to properties and equipment	8,086	[1]	36,659	[1]	344,557	[1]	48,534	[1]
Corporate	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Depreciation and amortization	789		888		1,499		1,895
Additions to properties and equipment	$49,747	[2]	$44,194	[2]	$111,597	[2]	$88,285	[2]

[1]	Included in Sub-Saharan Africa/Europe for the six months ended September 30, 2013 is $245.6 million related to vessels acquired through the acquisition of Troms Offshore.
[2]	Included in Corporate are additions to properties and equipment relating to vessels currently under construction which have not yet been assigned to a non-corporate reporting segment as of the dates presented.

Segment_Information_Geographic1

Segment Information, Geographical Data and Major Customers (Parenthetical) (Detail) (USD $)	3 Months Ended				6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Segment Reporting Information [Line Items]	'		'		'		'
Additions to properties and equipment	'		'		$220,309		$189,826
Sub-Saharan Africa/Europe	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Additions to properties and equipment	8,086	[1]	36,659	[1]	344,557	[1]	48,534	[1]
Sub-Saharan Africa/Europe \| Troms Offshore Supply AS	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Additions to properties and equipment	'		'		$245,600		'

[1]	Included in Sub-Saharan Africa/Europe for the six months ended September 30, 2013 is $245.6 million related to vessels acquired through the acquisition of Troms Offshore.

Comparison_of_Total_Assets_Det

Comparison of Total Assets (Detail) (USD $)	Sep. 30, 2013		Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013		Mar. 31, 2013
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	$4,754,579		$4,168,055
Investments in, at equity, and advances to unconsolidated companies	52,254		46,047
Marine	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	4,217,813		3,706,495
Investments in, at equity, and advances to unconsolidated companies	52,254		46,047
Americas \| Marine	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	930,475		885,470
Asia/Pacific \| Marine	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	487,850		607,546
Middle East/N. Africa \| Marine	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	584,805		507,124
Sub-Saharan Africa/Europe \| Marine	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	2,214,683		1,706,355
Segment Total \| Marine	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	4,270,067		3,752,542
Corporate	'		'
Segment and Geographic Distribution of Operations [Line Items]	'		'
Assets	$484,512	[1]	$415,513	[1]

[1]	Included in Corporate are vessels currently under construction which have not yet been assigned to a non-corporate reporting segment. The vessel construction costs will be reported in Corporate until the earlier of the vessels being assigned to a non-corporate reporting segment or the vessels' delivery. At September 30, 2013 and March 31, 2013, $306.7 million and $229.3 million, respectively, of vessel construction costs are included in Corporate.

Comparison_of_Total_Assets_Par

Comparison of Total Assets (Parenthetical) (Detail) (Corporate Vessels, USD $)	6 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Corporate Vessels	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'
Construction costs	$306.70	$229.30

Schedule_of_Segment_Reporting_

Schedule of Segment Reporting Information, Revenue by Vessel Class (Detail) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	$363,668	$309,822	$695,298	$599,916
Americas Fleet Deepwater Vessels	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	61,811	44,747	116,843	81,027
Percentage of revenue	17.00%	14.00%	17.00%	14.00%
Americas Fleet Towing-Supply/Supply	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	30,861	31,109	58,531	65,461
Percentage of revenue	8.00%	10.00%	8.00%	11.00%
Americas Fleet Other	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	9,257	6,460	16,799	13,478
Percentage of revenue	3.00%	2.00%	3.00%	2.00%
Americas Fleet	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	101,929	82,316	192,173	159,966
Percentage of revenue	28.00%	27.00%	28.00%	27.00%
Asia and Pacific Fleet Deepwater Vessels	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	19,923	24,592	44,215	49,929
Percentage of revenue	5.00%	8.00%	6.00%	8.00%
Asia/Pacific Fleet Towing-Supply/Supply	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	16,559	20,229	34,281	45,729
Percentage of revenue	5.00%	7.00%	5.00%	8.00%
Asia and Pacific Fleet Other	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	948	917	1,890	1,822
Asia and Pacific Fleet Other \| Maximum	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Percentage of revenue	1.00%	1.00%	1.00%	1.00%
Asia/Pacific Fleet	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	37,430	45,738	80,386	97,480
Percentage of revenue	10.00%	15.00%	11.00%	16.00%
Middle East/N.Africa Fleet Deepwater Vessels	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	15,732	12,275	31,584	23,559
Percentage of revenue	5.00%	4.00%	5.00%	4.00%
Middle East/N. Africa Fleet Towing-Supply/Supply	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	28,763	18,859	53,260	38,859
Percentage of revenue	8.00%	6.00%	8.00%	6.00%
Middle East and North Africa Fleet Other	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	875	917	1,739	2,083
Middle East and North Africa Fleet Other \| Maximum	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Percentage of revenue	1.00%	1.00%	1.00%	1.00%
Middle East/N.Africa	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	45,370	32,051	86,583	64,501
Percentage of revenue	13.00%	10.00%	13.00%	10.00%
Sub-Saharan Africa/Europe Fleet Deepwater Vessels	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	106,541	67,696	193,792	130,311
Percentage of revenue	29.00%	22.00%	28.00%	22.00%
Sub-Saharan Africa/Europe Fleet Towing-Supply/Supply	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	56,772	63,548	111,632	112,560
Percentage of revenue	16.00%	20.00%	16.00%	20.00%
Sub Saharan Africa And Europe Fleet Other	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	15,626	18,473	30,732	35,098
Percentage of revenue	4.00%	6.00%	4.00%	6.00%
Sub-Saharan Africa/Europe Fleet	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	178,939	149,717	336,156	277,969
Percentage of revenue	49.00%	48.00%	48.00%	47.00%
Worldwide Fleet Deepwater Vessels	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	204,007	149,310	386,434	284,826
Percentage of revenue	56.00%	48.00%	56.00%	47.00%
Worldwide Fleet Towing-Supply/Supply	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	132,955	133,745	257,704	262,609
Percentage of revenue	37.00%	43.00%	37.00%	44.00%
Worldwide Fleet Other	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	26,706	26,767	51,160	52,481
Percentage of revenue	7.00%	9.00%	7.00%	9.00%
Worldwide Fleet	'	'	'	'
Segment and Geographic Distribution of Operations [Line Items]	'	'	'	'
Vessel revenues	$363,668	$309,822	$695,298	$599,916
Percentage of revenue	100.00%	100.00%	100.00%	100.00%

Goodwill_Additional_Informatio

Goodwill - Additional Information (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2013
Goodwill - Additional Information (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013	Asia/Pacific	Sub-Saharan Africa/Europe
Goodwill [Line Items]	'	'	'	'
Goodwill impairment charge	'	'	$0	'
Goodwill	$339,982,000	$297,822,000	'	$42,200,000

Schedule_of_Goodwill_by_Report

Schedule of Goodwill by Reportable Segment (Detail) (USD $)	Sep. 30, 2013	Mar. 31, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Goodwill [Line Items]	'	'
Goodwill	$339,982	$297,822
Americas	'	'
Goodwill [Line Items]	'	'
Goodwill	114,237	114,237
Asia/Pacific	'	'
Goodwill [Line Items]	'	'
Goodwill	56,283	56,283
Sub-Saharan Africa/Europe	'	'
Goodwill [Line Items]	'	'
Goodwill	$169,462	$127,302

Sale_Leaseback_Arrangements_Ad

Sale/ Leaseback Arrangements - Additional Information (Detail) (USD $)	1 Months Ended	6 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
	M	M
	Vessel
Sale Leaseback Transaction [Line Items]	'	'
Number of vessels sold	2	'
Proceeds from sale	$65,600,000	$65,550,000
Deferred gain	31,300,000	31,300,000
Carrying value	$34,300,000	$34,300,000
Lease expiration Date	30-Sep-20	'
Length of extension period, months	24	24
Operating leases, term of contract	'	'7 years
Reacquisition percentage of original sales price	'	55.00%

Schedule_of_Future_Minimum_Lea

Schedule of Future Minimum Lease Payments (Detail) (USD $)	Sep. 30, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013
Sale Leaseback Transaction [Line Items]	'
Remaining six-months of 2014	$2,794
2015	5,588
2016	5,589
2017	5,589
2018	6,830
Thereafter	17,076
Total future lease payments	$43,466