XML 40 R27.htm IDEA: XBRL DOCUMENT v3.25.3

SHAREHOLDERS' EQUITY (Tables)

9 Months Ended

Sep. 30, 2025

SHAREHOLDERS' EQUITY.

Schedule of transactions related to restricted stock units under the 2016 Plan, the 2023 Plan and the 2025 Plan

The following table summarizes all transactions related to restricted stock units granted under the 2016 Plan, the 2023 Plan, and the 2025 Plan for the nine months ended September 30, 2025:

​	​	​	​	​	​	​
(in thousands, except share amounts)	​	​	Number of Shares of Common Stock/Restricted Stock Units	​	Weighted Average Grant Date Fair Value
Non-vested as of December 31, 2024	​	​	214,493	​	$	38.81
Granted	​	​	133,369	​	​	44.68
Vested (1)	​	​	(97,900)	​	​	49.29
Forfeited	​	​	—	​	​	—
Non-vested as of September 30, 2025	​	​	249,962	​	$	41.24

(1) Vested shares include 21,094 shares of common stock that vested and were withheld for employee taxes.

Schedule of additional data related to restricted share unit activity

The following table provides additional data related to restricted stock unit grants under the 2016 Plan, the 2023 Plan, and the 2025 Plan:

​	​	​	​
(in thousands, except weighted-average period in years)	​	September 30, 2025
Total compensation cost, net of estimated forfeitures, related to non-vested restricted stock unit awards not yet recognized, pre-tax	​	$	4,553
Weighted-average period in years over which restricted stock unit cost is expected to be recognized (in years)	​	​	1.5
Total grant date fair value of shares of common stock vested during the year	​	$	4,825

X

- Definition

Tabular disclosure of information pertaining to restricted stock units activity.

+ References

No definition available.

+ Details

Name:	mlr_ScheduleOfAdditionalInformationRelatedToRestrictedShareUnitActivityTableTextBlock
Namespace Prefix:	mlr_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration