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Stock-based Compensation Plans Grants Table (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended
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Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture | $ 11,900 |  |
Restricted Stock Units (RSUs) [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares | 7,127 | 82,565 | 129,081
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ 13.32 | $ 12.81 | $ 11.86
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture | $ 100 | $ 1,100 | $ 1,500
Employee Stock [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares | 32,916 | 35,325 | 40,286
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ 2.52 | $ 2.24 | $ 1.92
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture | $ 100 | $ 100 | $ 100
Phantom Share Units (PSUs) [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares | 3,567 | 1,254 | 180,987
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ 14.29 | $ 11.94 | $ 11.86
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture | $ 100 | $ 0 | $ 2,100
Market Based Performance Shares |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares |  | 4,187 | 234,199
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  | $ 14.26 | $ 15.39
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture |  | $ 100 | $ 3,600
Equity Option |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares |  | 8,115 | 423,405
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  | $ 3.08 | $ 3.05
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture |  | $ 0 | $ 1,300
Share-based Payment Arrangement, Tranche Two [Member] | Performance Shares [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares |  |  | 60,019
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  | $ 11.86
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture |  |  | $ 700
Share-based Payment Arrangement, Tranche Three [Member] | Performance Shares [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted, shares |  |  | 84,483
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  | $ 11.86
Shares Granted, Value, Share-based Payment Arrangement, before Forfeiture |  |  | $ 1,000

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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