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Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2021
Share-based Payment Arrangement [Abstract] |
Summary of Plan Pool of Shares | As of December 31, 2021, the pool of shares in the 2021 Plan is summarized as follows:
Maximum allowed for issuance | 19,952,329 |
Awards granted | 1,238,683 |
Awards forfeited | — |
Available for future awards | 18,713,646 |
Awards vested | — |
Schedule of Stock-based Compensation Plans | The table below summarizes certain data for our stock-based compensation plans (in millions):
| Successor |  | Predecessor
| From October 20, 2021 through December 31, 2021 |  | From July 1, 2021 through October 19, 2021
Stock-based compensation expense (1) | $ | 5.3 |  |  | $ | 9.3 |
Tax (expense) benefit for stock-based compensation (2) | $ | — |  |  | $ | — |
(1) Includes expense related to Profits Interests for the periods presented. Stock based compensation expense related to RSUs, PSUs and Director RSUs was immaterial for the periods presented (2) Tax (expense) benefit was zero related to Profits Interests expense
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions | The fair value of the PSUs is determined using a Monte Carlo simulation model determined on the grant date with the following assumptions:
MIR Stock Price | $ | 10.70 |
Expected volatility(1) | 41.12 | %
Risk-free interest rate(2) | 0.98 | %
Dividend yield | 0.00 | %
Fair value | $ | 7.91 |
(1) Expected volatility is based on historical volatilities from a group of comparable entities for a time period similar to that of the expected term. (2) The risk-free rate is based on an average of U.S. Treasury yields in effect at the time of grant corresponding with the expected term. The fair value of the Profits Interests are estimated based on a valuation model using Monte Carlo simulations, for the $12, $14, and $16 per share performance vesting conditions, with the following assumptions:
Cost of equity (1) | 8.5 | %
Risk-free interest rate (2) | 0.1 | %
Expected volatility (3) | 30.0 | %
Expected term (in years) (4) | 5
Average fair value of all profits interests | $ | 6.90 |
(1) Cost of equity based on a group of comparable entities (2) The risk-free rate is based on an average of U.S. Treasury yields in effect at the time of grant corresponding with the expected term. (3) Expected volatility is based on historical volatilities from a group of comparable entities for a time period similar to that of the expected term and the expected term. (4) Expected term is based on probability and expected timing of market events. The fair value of the Predecessor Shares was estimated using the Black-Scholes option-pricing model, with the following assumptions:
|  |  | Predecessor
|  |  | June 30, 2020 |  | June 30, 2019
Dividend yield |  |  | 0.0 | % |  | 0.0 | %
Risk-free interest rate (1) |  |  | 0.2 | % |  | 2.7 | %
Expected volatility (2) |  |  | 55.7 | % |  | 25.1 | %
Expected term (in years) (3) |  |  | 3 |  | 2
Fair value |  |  | $ | 0.37 |  |  | $ | 0.16 |
(1) The risk-free rate is based on an average of U.S. Treasury yields in effect at the time of grant corresponding with the expected term. (2) Expected volatility is based on historical volatilities from a group of comparable entities for a time period similar to that of the expected term and the expected term. (3) Expected term is based on probability and expected timing of market events.
Activity of RSUs, PSUs, and Director RSUs | Activity of our RSUs, PSUs and Director RSUs is as follows:
| RSUs |  | PSUs |  | Director RSUs
| Quantity |  | Weighted average grant date fair value |  | Quantity |  | Weighted average grant date fair value |  | Quantity |  | Weighted average grant date fair value
Beginning balance at Business Combination | — |  |  | $ | — |  |  | — |  |  | $ | — |  |  | — |  |  | $ | — |
Awards granted | 974,775 |  |  | $ | 10.48 |  |  | 229,006 |  |  | $ | 9.20 |  |  | 34,902 |  |  | $ | 10.48 |
Awards vested | — |  |  | $ | — |  |  | — |  |  | $ | — |  |  | — |  |  | $ | — |
Awards forfeited | — |  |  | $ | — |  |  | — |  |  | $ | — |  |  | — |  |  | $ | — |
Total awards outstanding at December 31, 2021 | 974,775 |  |  | $ | 10.48 |  |  | 229,006 |  |  | $ | 9.20 |  |  | 34,902 |  |  | $ | 10.48 |
Schedule of Unrecognized Compensation Cost | Unrecognized compensation cost and weighted average periods remaining for non-vested awards as of December 31, 2021 are as follows (in millions):
| Successor |
| From October 20, 2021 through December 31, 2021 | Weighted average period remaining for non-vested awards as of December 31, 2021
Unrecognized compensation cost |  |
RSUs | $ | 10.2 |  | 4 years
PSUs | 2.1 | 3 years
Director RSUs | 0.4 | 4 months
Total unrecognized compensation cost at December 31, 2021 | $ | 12.7 |  |
Share-based Payment Arrangement, Activity | A summary of restricted stock activity within the Company’s equity plans and changes for the years ended June 30, 2021, 2020 and 2019 and the Predecessor Stub Period, is as follows:
| Shares (in millions) |  | Weighted Average Grant- Date Fair Value |  | Total Fair Value (in millions)
Restricted Stock Awards |  |  |  |  |
Nonvested at June 30, 2019 | 0.4 |  |  | $ | 0.39 |  |  | $ | 0.2 |
Granted | 0.2 |  |  | 0.37 |  |  | 0.1 |
Vested | (0.1) |  |  | 0.27 |  |  | — |
Repurchased | (0.1) |  |  | 0.57 |  |  | (0.1) |
Nonvested at June 30, 2020 | 0.4 |  |  | $ | 0.41 |  |  | $ | 0.1 |
Granted | — |  |  | — |  |  | — |
Vested | (0.2) |  |  | 0.35 |  |  | (0.1) |
Repurchased | — |  |  | — |  |  | — |
Nonvested at June 30, 2021 | 0.2 |  |  | $ | 0.27 |  |  | $ | — |
Granted | — |  |  | — |  |  | — |
Vested | (0.2) |  |  | 0.27 |  |  | — |
Repurchased | — |  |  | — |  |  | — |
Nonvested at October 19, 2021 | — |  |  | $ | — |  |  | $ | — |

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- Definition Tabular disclosure of activity for award under share-based payment arrangement. Includes, but is not limited to, outstanding award at beginning and end of year, granted, exercised, forfeited, and weighted-average grant date fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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