PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Tables)

12 Months Ended

Mar. 31, 2019

Mar. 31, 2018

Defined Benefit Plan Disclosure [Line Items]

Schedule of Changes in Projected Benefit Obligations [Table Text Block]

	Pension Benefits						Other Postretirement Benefits
	Year ended March 31,						Year ended March 31,
	2019			2018			2019			2018
Change in projected benefit obligations
Projected benefit obligation at beginning of year	$	2,277,816		$	2,346,990		$	119,164		$	164,128
Service cost	3,292			4,505			227			391
Interest cost	79,446			75,189			4,039			4,393
Actuarial loss (gain)	48,931			19,110			(2,576		)	(17,780		)
Plan amendments	1,138			(1,939		)	—			(20,042		)
Participant contributions	196			187			833			885
Settlements	—			(3,233		)	—			—
Special termination benefits	4,032			—			—			—
Benefits paid	(176,398		)	(168,464		)	(12,232		)	(12,811		)
Currency translation adjustment	(3,719		)	5,471			—			—
Projected benefit obligation at end of year	$	2,234,734		$	2,277,816		$	109,455		$	119,164
Accumulated benefit obligation at end of year	$	2,229,188		$	2,272,505		$	109,455		$	119,164
Assumptions used to determine benefit obligations at end of year
Discount rate	2.54 - 3.88%			2.65 - 4.01%			3.77		%	3.93		%
Rate of compensation increase	3.50 - 4.50%			3.50 - 4.50%			N/A			N/A

Schedule of Changes in Fair Value of Plan Assets [Table Text Block]

	Pension Benefits						Other Postretirement Benefits
	Year ended March 31,						Year ended March 31,
	2019			2018			2019			2018
Change in fair value of plan assets
Fair value of plan assets at beginning of year	$	1,903,901		$	1,900,372		$	—		$	—
Actual return on plan assets	67,753			164,281			—			—
Settlements	—			(3,233		)	—			—
Participant contributions	196			187			833			885
Company contributions	4,580			5,124			11,399			11,926
Benefits paid	(176,398		)	(168,464		)	(12,232		)	(12,811		)
Currency translation adjustment	(3,921		)	5,634			—			—
Fair value of plan assets at end of year	$	1,796,111		$	1,903,901		$	—		$	—
Funded status (underfunded)
Funded status	$	(438,623	)	$	(373,915	)	$	(109,455	)	$	(119,164	)
Reconciliation of amounts recognized on the consolidated balance sheets
Pension asset—noncurrent	$	3,900		$	3,155		$	—		$	—
Accrued benefit liability—current	(742		)	(764		)	(10,758		)	(11,584		)
Accrued benefit liability—noncurrent	(441,781		)	(376,306		)	(98,697		)	(107,580		)
Net amount recognized	$	(438,623	)	$	(373,915	)	$	(109,455	)	$	(119,164	)
Reconciliation of amounts recognized on accumulated other comprehensive income
Prior service credits	$	780		$	(3,978	)	$	(14,497	)	$	(75,261	)
Actuarial losses (gains)	682,226			570,933			(67,985		)	(19,151		)
Income tax (benefits) expenses related to above items	(204,594		)	(205,250		)	42,016			42,016
Unamortized benefit plan costs (gains)	$	478,412		$	361,705		$	(40,466	)	$	(52,396	)

Schedule of components of net periodic benefit cost and postretirement benefit plan

	Pension Benefits									Other Postretirement Benefits
	Year Ended March 31,									Year Ended March 31,
	2019			2018			2017			2019			2018			2017
Components of net periodic pension cost
Service cost	$	3,292		$	4,505		$	6,538		$	227		$	391		$	716
Interest cost	79,446			75,189			72,638			4,039			4,393			4,987
Expected return on plan assets	(147,411		)	(152,346		)	(155,991		)	—			—			—
Amortization of prior service credit cost	(3,619		)	(2,841		)	(1,782		)	(4,655		)	(8,537		)	(13,464		)
Amortization of net loss	16,822			13,905			12,115			(9,851		)	(7,275		)	(6,588		)
Curtailment gain (loss)	—			29			—			—			(26,274		)	—
Settlements	—			523			—			—			—			—
Special termination benefits	4,032			—			—			—			—			—
Total net periodic benefit (income) expense	$	(47,438	)	$	(61,036	)	$	(66,482	)	$	(10,240	)	$	(37,302	)	$	(14,349	)
Assumptions used to determine net periodic pension cost
Discount rate	2.65 - 4.01%			2.87 - 4.06%			3.25 - 3.93%			3.93%			3.62 - 3.93%			3.73		%
Expected long-term rate on assets	5.00 - 8.00%			6.50 - 8.00%			6.50 - 8.00%			N/A			N/A			N/A
Rate of compensation increase	3.50 - 4.50%			3.50 - 4.50%			3.50 - 4.50%			N/A			N/A			N/A

Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block]

	Pension Benefits			Other Postretirement Benefits
Amounts expected to be recognized in FY 2020 net periodic benefit costs
Prior service credit	$	(1,114	)	$	(4,655	)
Actuarial loss	$	21,439		$	(9,767	)

Schedule of Expected Benefit Payments [Table Text Block]

Year	Pension Benefits		Other Postretirement Benefits*
2020	$	173,599	$	10,881
2021	168,172		10,575
2022	164,132		10,104
2023	161,925		9,558
2024	157,505		9,087
2025 - 2029	727,250		37,219

Schedule of Allocation of Plan Assets [Table Text Block]

		Actual Allocation
	Target Allocation
		March 31,
Asset Category	Fiscal 2019	2019		2018
Equity securities	40% - 50%	45	%	45	%
Fixed income securities	40% - 50%	48		48
Alternative investment funds	0% - 10%	5		5
Other	0% - 5%	2		2
Total		100	%	100	%

March 31, 2019
	Level 1		Level 2		Level 3		Total
Assets
Cash and cash equivalents	$	25,798	$	6,189	$	—	$	31,987
Equity securities
International	161,132		—		—		161,132
U.S. equity	8,464		—		—		8,464
U.S. commingled fund	489,463		—		—		489,463
International commingled fund	39,797		—		—		39,797
Fixed income securities
Corporate bonds	—		24,942		—		24,942
Government securities	—		109,306		—		109,306
U.S. commingled fund	654,269		—		—		654,269
Other
Insurance contracts	—		—		1,021		1,021
Total investment in securities—assets	$	1,378,923	$	140,437	$	1,021	$	1,520,381
U.S. equity commingled fund							4,690
International equity commingled fund							96,867
U.S. fixed income commingled fund							76,766
Private equity and infrastructure							95,760
Other							1,693
Total investment measured at NAV as a practical expedient							$	275,776
Receivables							1,238
Payables							(1,284		)
Total plan assets							$	1,796,111

March 31, 2018
	Level 1		Level 2		Level 3		Total
Assets
Cash and cash equivalents	$	25,559	$	6,670	$	—	$	32,229
Equity securities
International	164,033		—		—		164,033
U.S. equity	63,037		—		—		63,037
U.S. commingled fund	533,177		—		—		533,177
International commingled fund	46,147		—		—		46,147
Fixed income securities
Corporate bonds	—		118,474		—		118,474
Government securities	—		11,815		—		11,815
U.S. commingled fund	681,807		—		—		681,807
International commingled fund	—		—		—		—
Other fixed income	—		—		—		—
Other
Insurance contracts	—		—		1,256		1,256
Total investment in securities—assets	$	1,513,760	$	136,959	$	1,256	$	1,651,975
U.S. equity commingled fund							4,428
International equity commingled fund							44,779
U.S. fixed income commingled fund							105,721
Private equity and infrastructure							94,305
Other							1,598
Total investment measured at NAV as a practical expedient							$	250,831
Receivables							1,238
Payables							(143		)
Total plan assets							$	1,903,901

Scheduled of Effect of a 25 Basis Point Change in Discount Rates on Defined Benefit Obligations [Table Text Block]

		Pension Benefits			Other Postretirement Benefits
Increase of 25 basis points
Obligation	*	$	(56,167	)	$	(2,131	)
Net periodic expense		11			(223		)
Decrease of 25 basis points
Obligation	*	$	58,699		$	2,214
Net periodic expense		(3		)	231

Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]

	Other Postretirement Benefits
	One-Percentage- Point Increase		One-Percentage- Point Decrease
Net periodic expense	$	224	$	(206	)
Obligation	4,831		(4,448		)