EMPLOYEE RETIREMENT PLANS (Tables)

12 Months Ended

Mar. 31, 2017

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 March 31:

(In thousands)	2017			2016
Investments held in Rabbi Trust	$	8,759			8,811
Unrealized (loss) gains in carrying value of trust assets		(95	)		(208	)
Unrealized (loss) gains in carrying value of trust assets    are net of income tax expense of		(223	)		(168	)
Obligations under the supplemental plan		29,108			25,072

Minimum and Maximum Rate of Return Plan Assets

The below table summarizes the supplemental plan’s minimum and maximum rate of return objectives for plan assets:

	Minimum Expected Rate of Return on Plan Assets		Maximum Expected Rate of Return on Plan Assets
Equity securities		5%		7%
Debt securities		1%		3%
Cash and cash equivalents		0%		1%

Schedule of Minimum and Maximum Market Value of Plan Assets

The below table summarizes the supplemental plan’s minimum and maximum market value objectives for plan assets, which are based upon a five to ten year investment horizon:

	Minimum Market Value Objective for Plan Assets		Maximum Market Value Objective for Plan Assets
Equity securities		55%		75%
Debt securities		25%		45%
Percentage of debt securities allowed in below    investment grade bonds		0%		20%
Cash and cash equivalents		0%		10%

Schedule of Asset Allocations

The following table provides the target and actual asset allocations for the pension plan and the supplemental plan:

	Target			Actual as of 2017			Actual as of 2016
U.S. Pension plan:
Equity securities		—			—			—
Debt securities		100	%		98	%		95	%
Cash and other		—			2	%		5	%
Total		100	%		0	%		100	%
Supplemental plan:
Equity securities		65	%		59	%		58	%
Debt securities		35	%		37	%		39	%
Cash and other		—			4	%		3	%
Total		100	%		100	%		100	%

Fair Value Hierarchy of Plan Assets

The fair value hierarchy for the pension plans and supplemental plan assets measured at fair value as of March 31, 2017, are as follows:

(In thousands)	Fair Value		Quoted prices in active markets (Level 1)		Significant observable inputs (Level 2)		Significant unobservable inputs (Level 3)		Measured at Net Asset Value
Pension plan measured at fair value:
Debt securities:
Government securities	$	3,770		3,770		—		—		—
Collateralized mortgage securities		2,537		—		2,537		—		—
Corporate debt securities		47,871		—		47,871		—		—
Foreign debt securities		—		—		—		—		—
Cash and cash equivalents		989		345		644		—		—
Other		1,298		100		1,198		—		—
Total	$	56,465		4,215		52,250		—		—
Accrued income		681		681		—		—		—
Total fair value of plan assets	$	57,146		4,896		52,250		—		—
Supplemental plan measured at fair value:
Equity securities:
Common stock	$	3,561		3,561		—		—		—
Foreign stock		132		132		—		—		—
American depository receipts		1,387		1,387		—		—		—
Preferred American depository receipts		20		20		—		—		—
Real estate investment trusts		76		76		—		—		—
Debt securities:
Government debt securities		1,613		832		781		—		—
Open ended mutual funds		1,648		—		—		—		1,648
Cash and cash equivalents		323		15		236		—		72
Total	$	8,760		6,023		1,017		—		1,720
Other pending transactions		—		—		—		—		—
Total fair value of plan assets	$	8,760		6,023		1,017		—		1,720

The following table provides the fair value hierarchy for the pension plans and supplemental plan assets measured at fair value as of March 31, 2016:

(In thousands)	Fair Value		Quoted prices in active markets (Level 1)		Significant observable inputs (Level 2)			Significant unobservable inputs (Level 3)		Measured at Net Asset Value
Pension plan measured at fair value:
Debt securities:
Government securities	$	3,104		3,104		—			—		—
Collateralized mortgage securities		47		—		47			—		—
Corporate debt securities		48,378		—		48,378			—		—
Foreign debt securities		1,499		—		1,499			—		—
Cash and cash equivalents		2,247		346		1,901			—		—
Other		1,077		64		1,013			—		—
Total	$	56,352		3,514		52,838			—		—
Accrued income		822		822		—			—		—
Total fair value of plan assets	$	57,174		4,336		52,838			—		—
Supplemental plan measured at fair value:
Equity securities:
Common stock	$	3,290		3,290		—			—		—
Foreign stock		159		159		—			—		—
American depository receipts		1,311		1,311		—			—		—
Preferred American depository receipts		13		13		—			—		—
Real estate investment trusts		61		61		—			—		—
Debt securities:
Government debt securities		1,711		972		739			—		—
Open ended mutual funds		1,663		—		—			—		1,663
Cash and cash equivalents		343		13		282			—		48
Total	$	8,551		5,819		1,021			—		1,711
Other pending transactions		260		291		(49	)		—		18
Total fair value of plan assets	$	8,811		6,110		972			—		1,729

Change in Plan Assets and Obligations

Changes in plan assets and obligations during the years ended March 31, 2017 and 2016 and the funded status of the U.S. defined benefit pension plan, Norway’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 as “Other Benefits”) at March 31, are as follows:

	Pension Benefits						Other Benefits
(In thousands)	2017			2016			2017			2016
Change in benefit obligation:
Benefit obligation at beginning of year	$	95,830			98,490			5,573			23,926
Service cost		1,182			1,372			81			212
Interest cost		3,814			3,781			201			584
Participant contributions		—			—			411			447
Acquisition		—			(440	)		—			—
Plan amendment		—			—			—			(15,961	)
Plan settlement		—			—			—			—
Benefits paid		(4,895	)		(4,726	)		(1,170	)		(1,043	)
Actuarial (gain) loss		2,082			(2,583	)		(285	)		(2,592	)
Foreign currency exchange rate changes		(72	)		(64	)		—			—
Benefit obligation at end of year		97,941			95,830			4,811			5,573
Change in plan assets:
Fair value of plan assets at beginning of year	$	57,174			60,854			—			—
Actual return		577			(6	)		—			—
Expected return		51			43			—			—
Actuarial loss		(148	)		(134	)		—			—
Administrative expenses		(27	)		(36	)		—			—
Acquisition		—			(225	)		—			—
Employer contributions		4,465			1,445			759			596
Participant contributions		—			—			411			447
Plan settlement		—			—			—			—
Benefits paid		(4,895	)		(4,727	)		(1,170	)		(1,043	)
Foreign currency exchange rate changes		(51	)		(40	)		—			—
Fair value of plan assets at end of year		57,146			57,174			—			—
Payroll tax unrecognized in benefit obligation at end of year		83			84			—			—
Unfunded status at end of year	$	(40,878	)		(38,740	)		(4,811	)		(5,573	)
Net amount recognized in the balance sheet    consists of:
Current liabilities	$	(1,791	)		(993	)		(418	)		(818	)
Noncurrent liabilities		(39,087	)		(37,747	)		(4,393	)		(4,755	)
Net amount recognized	$	(40,878	)		(38,740	)		(4,811	)		(5,573	)

Schedule of Projected and Accumulated Benefit Obligation

The following table provides the projected benefit obligation and accumulated benefit obligation for the pension plans:

(In thousands)	2017		2016
Projected benefit obligation	$	97,941		95,830
Accumulated benefit obligation		94,467		91,388

Schedule of Accumulated Benefit Obligation in Excess of Plan Assets

The following table provides information for pension plans with an accumulated benefit obligation in excess of plan assets (includes both the pension plans and supplemental plan):

(In thousands)	2017		2016
Projected benefit obligation	$	97,941		95,830
Accumulated benefit obligation		94,467		91,388
Fair value of plan assets		57,146		57,174

Schedule of Net Periodic Benefit Cost

Net periodic benefit cost for the pension plans and the supplemental plan for the fiscal years ended March 31 include the following components:

(In thousands)	2017			2016			2015
Service cost	$	1,182			1,371			825
Interest cost		3,814			3,781			3,873
Expected return on plan assets		(2,246	)		(2,163	)		(2,741	)
Administrational expenses		28			36			—
Payroll tax of net pension costs		56			66			—
Amortization of prior service cost		—			36			50
Amortization of net actuarial losses		32			24			—
Recognized actuarial loss		1,785			2,269			988
Settlement (gain)		—			(245	)		—
Net periodic pension cost	$	4,651			5,175			2,995

Schedule of Net Periodic Benefit Cost for Postretirement Health Care and Life Insurance Plan

Net periodic benefit cost for the postretirement health care and life insurance plan for the fiscal years ended March 31 include the following components:

(In thousands)	2017			2016			2015
Service cost	$	81			212			273
Interest cost		201			584			904
Amortization of prior service cost		(4,346	)		(2,996	)		(2,032	)
Recognized actuarial (gain)		(1,138	)		(1,040	)		(1,299	)
Net periodic postretirement benefit	$	(5,202	)		(3,240	)		(2,154	)

Schedule of Other Changes in Plan Assets and Benefit Obligations Recognized in OCI

Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss for the fiscal years ended March 31 include the following components:

	Pension Benefits						Other Benefits
(In thousands)	2017			2016			2017			2016
Change in benefit obligation
Net (gain) loss	$	3,821			(343	)		(285	)		(2,592	)
Settlement loss		—			—			—			—
Amortization of prior service (cost) credit		—			(36	)		4,346			2,996
Amortization of net (loss) gain		(1,785	)		(2,269	)		1,138			1,040
Prior service (cost) arising during period		—			—			—			(15,961	)
Total recognized in other comprehensive (income)      loss, before tax	$	2,036			(2,648	)		5,199			(14,517	)
Net of tax		1,323			(1,721	)		3,379			(9,436	)

Schedule of Amounts Recognized in Accumulated Other Comprehensive Income (Loss)

Amounts recognized as a component of accumulated other comprehensive income (loss) as of March 31, 2017 are as follows:

(In thousands)	Pension Benefits			Other Benefits
Unrecognized actuarial (loss) gain	$	(21,204	)		7,318
Unrecognized prior service credit		—			13,207
Pre-tax amount included in accumulated other    comprehensive (loss) income	$	(21,204	)		20,525

Schedule of Expected Amounts Net Periodic Benefit Costs

The company expects to recognize the following amounts as a component of net periodic benefit costs during the next fiscal year:

(In thousands)	Pension Benefits			Other Benefits
Unrecognized actuarial (loss) gain	$	(2,295	)		993
Unrecognized prior service credit		—			2,780

Schedule of Assumptions

Assumptions used to determine net benefit obligations for the fiscal years ended March 31, are as follows:

	Pension Benefits						Other Benefits
	2017			2016			2017			2016
Discount rate		4.25	%		4.15	%		4.25	%		4.00	%
Rates of annual increase in compensation levels		3.00	%		3.00	%	N/A			N/A

Assumptions used to determine net periodic benefit costs for the fiscal years ended March 31, are as follows:

	Pension Benefits									Other Benefits
	2017			2016			2015			2017			2016			2015
Discount rate		4.15	%		4.00	%		4.75	%		4.00	%		4.00	%		4.75	%
Expected long-term rate of return on assets		4.10	%		3.70	%		5.00	%	N/A			N/A			N/A
Rates of annual increase in compensation levels		3.00	%		3.00	%		3.00	%	N/A			N/A			N/A

Schedule of Expected Benefit Payments

Based upon the assumptions used to measure the company’s qualified pension and postretirement benefit obligations at March 31, 2017, including pension and postretirement benefits attributable to estimated future employee service, the company expects that benefits to be paid over the next ten years will be as follows:

	(In thousands)
Year ending March 31,	Pension Benefits		Other Benefits
2018	$	6,746		418
2019		6,931		415
2020		8,504		429
2021		7,358		411
2022		7,318		404
2023 – 2027		37,620		1,765
Total 10-year estimated future benefit payments	$	74,477		3,842

Assumed Health Care Cost Trends Rates

The following table discloses the assumed health care cost trends used in measuring the accumulated postretirement benefit obligation and net periodic postretirement benefit cost at March 31, 2017 for pre-65 medical and prescription drug coverage, including expected future trend rates.

	Pre-65
Year ending March 31, 2017:
Accumulated postretirement benefit obligation		7.60	%
Net periodic postretirement benefit obligation		7.75	%
Ultimate health care cost trend		4.54	%
Ultimate year health care cost trend rate is achieved		2038
Year ending March 31, 2018:
Net periodic postretirement benefit obligation		7.60	%

One-Percentage Rate Change in Assumed Health Care Cost Trend Rates and Its Effects on Accumulated Postretirement Benefit Obligation

A one-percentage rate increase (decrease) in the assumed health care cost trend rates has the following effects on the accumulated postretirement benefit obligation as of March 31:

(In thousands)	1% Increase		1% Decrease
Accumulated postretirement benefit obligation	$	215,686		(195,172	)
Aggregate service and interest cost		15,486		(13,842	)

Number of Shares of Tidewater Common Stock Held

The plan held the following number of shares of Tidewater common stock as of March 31:

	2017		2016
Number of shares of Tidewater common stock held by 401(k) plan		291,957		351,675

Plan 401 k

Amounts Charged to Expense Related to Contribution Plans

The amounts charged to expense related to the above defined contribution plans, for the fiscal years ended March 31, are as follows:

(In thousands)	2017		2016		2015
Defined contribution plans expense, net of forfeitures	$	2,660		3,443		4,216
Defined contribution plans forfeitures		149		202		52

Multinational Retirement Plan

Amounts Charged to Expense Related to Contribution Plans

The amounts charged to expense related to the multinational retirement plan and multinational savings plan contributions, for the fiscal years ended March 31, are as follows:

(In thousands)	2017		2016		2015
Multinational plan expense	$	260		596		494