Amount of write-off for accumulated net actuarial losses related to the disposal group's pension plan.

No definition available.

Name:	mod_DisposalGroupWriteOffOfNetActuarialLosses
Namespace Prefix:	mod_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount classified as cash and cash equivalents attributable to disposal group held for sale or disposed of.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 205
-SubTopic 20
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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Details

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Balance Type:
Period Type:

- Details

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General (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
General (Details) - USD ($) $ in Millions	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Apr. 30, 2021
Sale of Business [Abstract]
Loss on sale of business	$ (6.6)	$ 0.0
Air-Cooled Automotive Business [Member] \| Held for Sale [Member]
Sale of Business [Abstract]
Loss on sale of business	(6.6)
Write-off of net actuarial losses	$ 1.7
Cash transferred to buyer				$ 5.9
Net sales			$ 63.0