Pension and Other Benefits (Details) - USD ($)	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Change in pension liability and postretirement obligations, net of tax	$ 10,108,000	$ (4,685,000)	$ (20,162,000)
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets	0	127,726,000
Defined Benefit Plan, Business Combinations and Acquisitions, Benefit Obligation	72,638,000	168,855,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	317,868,000
Fair value of plan assets at end of year	321,440,000	317,868,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Change in pension liability and postretirement obligations, net of tax	(57,000)	2,452,000	82,000
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	421,147,000	261,540,000
Service cost	1,779,000	2,187,000	2,153,000
Interest cost	16,648,000	13,926,000	9,850,000
Actuarial (gain) loss	(4,475,000)	(6,979,000)
Benefits paid	(31,757,000)	(19,196,000)
Foreign exchange rate changes	(3,226,000)	814,000
Benefit obligation at end of year	471,871,000	421,147,000	261,540,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	317,868,000	204,201,000
Actual gain (loss) on plan assets	30,164,000	(691,000)
Employer contribution	6,140,000	5,936,000
Benefits paid	(31,757,000)	(19,196,000)
Foreign exchange rate changes	(92,000)	(108,000)
Fair value of plan assets at end of year	321,440,000	317,868,000	204,201,000
Funded status	(150,431,000)	(103,279,000)
Unrecognized actuarial loss	(83,030,000)	(98,630,000)
Unrecognized prior service cost	8,000	15,000
Net amount recognized	(67,393,000)	(4,634,000)
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued liabilities	(3,310,000)	(812,000)
Other non-current liabilities	(147,121,000)	(102,467,000)
Deferred tax effect of accumulated other comprehensive loss	21,102,000	27,256,000
Accumulated other comprehensive loss	61,936,000	71,389,000
Net amount recognized	(67,393,000)	(4,634,000)
Postretirement Benefit Plans
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	5,144,000	6,234,000
Interest cost	152,000	189,000	209,000
Actuarial (gain) loss	841,000	887,000
Benefits paid	344,000	392,000
Benefit obligation at end of year	4,111,000	5,144,000	$ 6,234,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Benefits paid	344,000	392,000
Funded status	(4,111,000)	(5,144,000)
Unrecognized actuarial loss	(23,000)	818,000
Net amount recognized	(4,134,000)	(4,326,000)
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued liabilities	(519,000)	(604,000)
Other non-current liabilities	(3,592,000)	(4,540,000)
Deferred tax effect of accumulated other comprehensive loss	865,000	1,182,000
Accumulated other comprehensive loss	(888,000)	(364,000)
Net amount recognized	$ (4,134,000)	$ (4,326,000)