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Stock Compensation Plans and Other Employee Benefit Plans (Narrative) (Details) - USD ($) | 12 Months Ended | 84 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2022 | May 31, 2022 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares approved for issuance (in shares) |  |  |  |  | 1,200,000 |
Shares available for future grants (in shares) | 1,600,000 |  |  | 1,600,000 |  |
Number of stock options granted (in shares) |  |  |  | 0 |  |
Stock-based compensation expense | $ 31,700,000 | $ 16,200,000 | $ (4,900,000) |  |  |
Tax benefit (expense) from stock-based compensation arrangements | 7,000,000 | 3,700,000 | (914,000,000) |  |  |
Aggregate intrinsic value of options exercised | 6,700,000 | 11,700,000 | 4,100,000 |  |  |
Actual tax benefit realized from option exercises | 1,800,000 | 3,100,000 | 1,100,000 |  |  |
Cash received from option exercises | 5,200,000 | 14,000,000 | 9,700,000 |  |  |
Excess (deficit) tax benefit over estimate | (580,000) | (40,000) | 848,000 |  |  |
Unrecognized compensation cost | $ 37,800,000 |  |  | $ 37,800,000 |  |
Unrecognized compensation cost, period for recognition | 2 years |  |  |  |  |
Fair value of shares vested | $ 4,500,000 | 1,500,000 | 14,700,000 |  |  |
Expense for employer contribution to plan | 16,200,000 | 15,600,000 | 13,800,000 |  |  |
Cash Incentive and Retention Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Expense related to plan | 0 | 0 | 0 |  |  |
Cash awards paid | 0 | $ 0 | $ 0 |  |  |
Cash awards outstanding | $ 0 |  |  | $ 0 |  |
Directors Deferred Fee and Stock Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Increase in shares authorized (in shares) |  |  | 200,000 |  |  |
Issued to directors (in shares) | 59,174 | 23,909 | 19,928 |  |  |
Obligation to issue (in shares) | 313,409 |  |  | 313,409 |  |
Available for future issuance under DDFS Plan (in shares) | 121,119 |  |  | 121,119 |  |
Stock Options |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Term | 10 years |  |  |  |  |
Stock Options | Minimum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period | 3 years |  |  |  |  |
Stock Options | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period | 5 years |  |  |  |  |
Restricted Shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares outstanding (in shares) | 610,155 | 476,813 | 234,794 | 610,155 |  | 144,328
Restricted Shares | Minimum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period | 1 year |  |  |  |  |
Restricted Shares | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period | 5 years |  |  |  |  |
LTIP Awards |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period | 3 years |  |  |  |  |
Term | 7 years |  |  |  |  |
LTIP Awards | Minimum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of performance based award payouts | 0.00% |  |  |  |  |
LTIP Awards | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of performance based award payouts | 150.00% |  |  |  |  |
Performance Shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period | 3 years |  |  |  |  |
Performance period | 3 years |  |  |  |  |
Shares outstanding (in shares) | 545,379 | 557,255 | 482,608 | 545,379 |  | 465,515
Performance Shares | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares outstanding (in shares) | 800,000 |  |  | 800,000 |  |
ESPP |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of purchase price of shares | 95.00% |  |  |  |  |
Employee stock purchase plan issuance (in shares) | 40,421 | 44,021 | 75,763 |  |  |
Compensation expense employee stock purchase plan | $ 0 | $ 0 | $ 0 |  |  |
Increase in shares authorized (in shares) |  | 200,000 |  |  |  |
Common stock obligation to issue (in shares) | 8,638 |  |  | 8,638 |  |
Available for future grants under ESPP (in shares) | 212,472 |  |  | 212,472 |  |

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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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