Fair Value Measurements (Assets and liabilities measured at fair value on recurring bases) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Mar. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities	$ 7,862	$ 7,028
Marketable securities | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities	7,862	7,028
Marketable securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities		0
Marketable securities | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities		0
Variable Annuity [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Annuity contract	2,036	2,285
Variable Annuity [Member] | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Annuity contract		0
Variable Annuity [Member] | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Annuity contract	2,036	2,285
Variable Annuity [Member] | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Annuity contract		0
Foreign exchange contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	(64)	(70)
Foreign exchange contracts | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Foreign exchange contracts | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	(64)	(70)
Foreign exchange contracts | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Term loan
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Term loan	(281,865)	(310,463)
Term loan | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Term loan		0
Term loan | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Term loan	(281,865)	(310,463)
Term loan | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Term loan		0
Assets [Member] | Interest Rate Swap [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		1,213
Assets [Member] | Interest Rate Swap [Member] | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Assets [Member] | Interest Rate Swap [Member] | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		1,213
Assets [Member] | Interest Rate Swap [Member] | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Assets [Member] | Cross Currency Interest Rate Contract [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	2,148	2,476
Assets [Member] | Cross Currency Interest Rate Contract [Member] | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Assets [Member] | Cross Currency Interest Rate Contract [Member] | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	2,148	2,476
Assets [Member] | Cross Currency Interest Rate Contract [Member] | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Liability [Member] | Interest Rate Swap [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	(1,531)
Liability [Member] | Interest Rate Swap [Member] | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities
Liability [Member] | Interest Rate Swap [Member] | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	(1,531)
Liability [Member] | Interest Rate Swap [Member] | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities
Liability [Member] | Cross Currency Interest Rate Contract [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	(8,386)	(16,184)
Liability [Member] | Cross Currency Interest Rate Contract [Member] | Quoted Prices in Active Markets for Indentical Assets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		0
Liability [Member] | Cross Currency Interest Rate Contract [Member] | Significant Other Observable Inputs (Level 2)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities	(8,386)	(16,184)
Liability [Member] | Cross Currency Interest Rate Contract [Member] | Significant unobservable Inputs (Level 3)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities		$ 0