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Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Mar. 31, 2017
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Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | $ 57,536 |
Total fair value of plan assets | [1] | 8,908 |
Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | $ 57,146
Total fair value of plan assets |  |  | 8,759
Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 56,928 |
Accrued income |  | 608 |
Total fair value of plan assets |  | 57,536 |
Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 56,465
Accrued income |  |  | 681
Total fair value of plan assets |  |  | 57,146
Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 8,909 |
Other pending transactions |  | (1) |
Total fair value of plan assets |  | 8,908 |
Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 8,760
Total fair value of plan assets |  |  | 8,760
Measured At Net Asset Value | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,725 |
Total fair value of plan assets |  | 1,725 |
Measured At Net Asset Value | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,720
Total fair value of plan assets |  |  | 1,720
US Government Agencies Debt Securities | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 4,238 |
US Government Agencies Debt Securities | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 3,770
US Government Agencies Debt Securities | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,692 |
US Government Agencies Debt Securities | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,613
Collateralized mortgage securities | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,032 |
Collateralized mortgage securities | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 2,537
Corporate Debt Securities | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 49,420 |
Corporate Debt Securities | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 47,871
Cash and Cash Equivalents | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 834 |
Cash and Cash Equivalents | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 989
Cash and Cash Equivalents | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 246 |
Cash and Cash Equivalents | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 323
Cash and Cash Equivalents | Measured At Net Asset Value | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 49 |
Cash and Cash Equivalents | Measured At Net Asset Value | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 72
Common stock | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 3,599 |
Common stock | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 3,561
Foreign Stock | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 183 |
Foreign Stock | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 132
American Depository Receipts | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,429 |
American Depository Receipts | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,387
Preferred American Depository Receipts | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 12 |
Preferred American Depository Receipts | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 20
Real Estate Investment Trusts | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 72 |
Real Estate Investment Trusts | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 76
Open Ended Mutual Funds | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,676 |
Open Ended Mutual Funds | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,648
Open Ended Mutual Funds | Measured At Net Asset Value | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,676 |
Open Ended Mutual Funds | Measured At Net Asset Value | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,648
Other | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,404 |
Other | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,298
Quoted Prices In Active Markets (Level 1) | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 4,629 |
Accrued income |  | 608 |
Total fair value of plan assets |  | 5,237 |
Quoted Prices In Active Markets (Level 1) | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 4,215
Accrued income |  |  | 681
Total fair value of plan assets |  |  | 4,896
Quoted Prices In Active Markets (Level 1) | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 6,173 |
Other pending transactions |  | (1) |
Total fair value of plan assets |  | 6,172 |
Quoted Prices In Active Markets (Level 1) | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 6,023
Total fair value of plan assets |  |  | 6,023
Quoted Prices In Active Markets (Level 1) | US Government Agencies Debt Securities | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 4,238 |
Quoted Prices In Active Markets (Level 1) | US Government Agencies Debt Securities | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 3,770
Quoted Prices In Active Markets (Level 1) | US Government Agencies Debt Securities | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 851 |
Quoted Prices In Active Markets (Level 1) | US Government Agencies Debt Securities | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 832
Quoted Prices In Active Markets (Level 1) | Cash and Cash Equivalents | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 219 |
Quoted Prices In Active Markets (Level 1) | Cash and Cash Equivalents | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 345
Quoted Prices In Active Markets (Level 1) | Cash and Cash Equivalents | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 27 |
Quoted Prices In Active Markets (Level 1) | Cash and Cash Equivalents | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 15
Quoted Prices In Active Markets (Level 1) | Common stock | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 3,599 |
Quoted Prices In Active Markets (Level 1) | Common stock | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 3,561
Quoted Prices In Active Markets (Level 1) | Foreign Stock | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 183 |
Quoted Prices In Active Markets (Level 1) | Foreign Stock | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 132
Quoted Prices In Active Markets (Level 1) | American Depository Receipts | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,429 |
Quoted Prices In Active Markets (Level 1) | American Depository Receipts | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,387
Quoted Prices In Active Markets (Level 1) | Preferred American Depository Receipts | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 12 |
Quoted Prices In Active Markets (Level 1) | Preferred American Depository Receipts | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 20
Quoted Prices In Active Markets (Level 1) | Real Estate Investment Trusts | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 72 |
Quoted Prices In Active Markets (Level 1) | Real Estate Investment Trusts | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 76
Quoted Prices In Active Markets (Level 1) | Other | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 172 |
Quoted Prices In Active Markets (Level 1) | Other | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 100
Significant Observable Inputs (Level 2) | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 52,299 |
Total fair value of plan assets |  | 52,299 |
Significant Observable Inputs (Level 2) | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 52,250
Total fair value of plan assets |  |  | 52,250
Significant Observable Inputs (Level 2) | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,011 |
Total fair value of plan assets |  | 1,011 |
Significant Observable Inputs (Level 2) | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 1,017
Total fair value of plan assets |  |  | 1,017
Significant Observable Inputs (Level 2) | US Government Agencies Debt Securities | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 841 |
Significant Observable Inputs (Level 2) | US Government Agencies Debt Securities | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 781
Significant Observable Inputs (Level 2) | Collateralized mortgage securities | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 1,032 |
Significant Observable Inputs (Level 2) | Collateralized mortgage securities | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 2,537
Significant Observable Inputs (Level 2) | Corporate Debt Securities | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 49,420 |
Significant Observable Inputs (Level 2) | Corporate Debt Securities | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 47,871
Significant Observable Inputs (Level 2) | Cash and Cash Equivalents | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 615 |
Significant Observable Inputs (Level 2) | Cash and Cash Equivalents | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 644
Significant Observable Inputs (Level 2) | Cash and Cash Equivalents | Supplemental Executive Retirement Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | 170 |
Significant Observable Inputs (Level 2) | Cash and Cash Equivalents | Supplemental Executive Retirement Plan | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | 236
Significant Observable Inputs (Level 2) | Other | Pension Plans, Defined Benefit |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  | $ 1,232 |
Significant Observable Inputs (Level 2) | Other | Pension Plans, Defined Benefit | Predecessor |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair value of plan assets |  |  | $ 1,198
[1] | The company plans to liquidate the rabbi trust (valued at $8.9 million as of December 31, 2017) in advance of paying a lump sum benefit to the former CEO in April 2018 of $9.6 million.

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