CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Parenthetical) - USD ($) $ in Thousands	4 Months Ended	5 Months Ended	12 Months Ended
Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Mar. 31, 2017
Unrealized gains (losses) on available-for-sale securities, tax		$ 0	$ 0
Change in loss on derivative contract, tax		0	0
Change in supplemental executive retirement plan pension liability, tax		0	0
Change in Pension Plan minimum liability, tax		0	0
Change in Other Benefit Plan minimum liability, tax		$ 0	$ 0
Predecessor
Unrealized gains (losses) on available-for-sale securities, tax	$ 0			$ 61
Change in loss on derivative contract, tax	0			823
Change in supplemental executive retirement plan pension liability, tax	0			(927)
Change in Pension Plan minimum liability, tax	0			215
Change in Other Benefit Plan minimum liability, tax	$ 0			$ (2,046)

Other Comprehensive Income Pension Plan Minimum Liability Adjustment Tax Period Increase Decrease

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- Definition

Other Comprehensive Income Supplemental Executive Retirement Plan Minimum Liability Adjustment Tax Period Increase Decrease

+ References

No definition available.

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- Definition

Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

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- Definition

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

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