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Employee Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of Share-based Compensation, Shares Reserved for Future Issuance | The following table sets forth the number of shares of Common Stock reserved for future issuance under the Company’s long-term equity incentive plans:
| December 31,
| 2020 |  | 2019
Outstanding stock options and warrants | 552,373 |  |  | 599,902 |
Possible future issuance under equity incentive plans | 1,926,324 |  |  | 2,016,659 |
| 2,478,697 |  |  | 2,616,561 |
Disclosure of Share-based Compensation Arrangements by Share-based Payment Award | The following table sets forth stock option activity:
| Options Outstanding
| Number of Options |  | Weighted Average Exercise Price
Stock options outstanding at December 31, 2017 | 640,822 |  |  | $ | 45.29 |
Exercised | (44,304) |  |  | 40.15 |
Stock options outstanding at December 31, 2018 | 596,518 |  |  | 45.67 |
Exercised | (9,026) |  |  | 39.53 |
Forfeited | (2,590) |  |  | 48.79 |
Stock options outstanding at December 31, 2019 | 584,902 |  |  | 45.75 |
Exercised | (42,163) |  |  | 41.10 |
Forfeited | (5,366) |  |  | 50.82 |
Stock options outstanding at December 31, 2020 (1) (2) | 537,373 |  |  | $ | 46.07 |
__________ (1)The outstanding options at December 31, 2020 had a weighted average remaining life of 5.0 years. (2)The Company had 496,656 options exercisable at December 31, 2020 with a weighted average exercise price of $45.54, weighted average remaining life of 4.9 years and intrinsic value of $0.1 million. Of these exercisable options, 436,880 had exercise prices higher than the market price of our Common Stock at December 31, 2020.
Schedule of NonQualified Deferred Compensation Liability | The following table sets forth our deferred compensation liability:
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Beginning deferred compensation liability | $ | 2,345 |  |  | $ | 1,849 |  |  | $ | 2,388 |
Mark-to-market adjustment to deferred compensation (in general and administrative expenses) | 228 |  |  | 496 |  |  | (182) |
Distributions from deferred compensation plans | — |  |  | — |  |  | (357) |
Total deferred compensation liability | $ | 2,573 |  |  | $ | 2,345 |  |  | $ | 1,849 |
Time-Based Restricted Stock [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of Share-based Compensation, Restricted Stock Units Award Activity | The following table sets forth time-based restricted stock activity:
| Number of Shares |  | Weighted Average Grant Date Fair Value
Restricted shares outstanding at December 31, 2017 | 172,246 |  |  | $ | 46.46 |
Awarded and issued (1) | 94,984 |  |  | 43.01 |
Vested (2) | (73,307) |  |  | 44.19 |
Forfeited | (2,684) |  |  | 45.89 |
Restricted shares outstanding at December 31, 2018 | 191,239 |  |  | 45.62 |
Awarded and issued (1) | 103,590 |  |  | 45.98 |
Vested (2) | (73,036) |  |  | 45.79 |
Forfeited | (3,642) |  |  | 46.07 |
Restricted shares outstanding at December 31, 2019 | 218,151 |  |  | 45.73 |
Awarded and issued (1) | 83,116 |  |  | 44.88 |
Vested (2) | (88,326) |  |  | 45.86 |
Forfeited | (3,751) |  |  | 45.78 |
Restricted shares outstanding at December 31, 2020 | 209,190 |  |  | $ | 45.34 |
__________ (1)The weighted average fair value at grant date of time-based restricted stock issued during the years ended December 31, 2020, 2019 and 2018 was $3.7 million, $4.8 million and $4.1 million, respectively. (2)The vesting date fair value of time-based restricted stock that vested during the years ended December 31, 2020, 2019 and 2018 was $3.9 million, $3.3 million and $3.2 million, respectively. Vested shares include those shares surrendered by employees to satisfy tax withholding obligations in connection with such vesting.
Total Return-Based Restricted Stock [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions | The fair values of the total return-based restricted stock granted were determined at the grant dates using a Monte Carlo simulation model and the following assumptions:
| 2020 |  | 2019 |  | 2018
Risk free interest rate (1) | 0.9 | % |  | 2.4 | % |  | 2.3 | %
Common stock dividend yield (2) | 3.9 | % |  | 4.4 | % |  | 3.9 | %
Expected volatility (3) | 20.4 | % |  | 27.3 | % |  | 41.1 | %
__________ (1)Represents the interest rate as of the grant date on US treasury bonds having the same life as the estimated life of the total return-based restricted stock grants. (2)The dividend yield is calculated utilizing the then current regular dividend rate for a one-year period and the average per share price of Common Stock during the three-month period preceding the date of grant. (3)Based on the historical volatility of Common Stock over a period relevant to the related total return-based restricted stock grant.
Schedule of Share-based Compensation, Restricted Stock Units Award Activity | The following table sets forth total return-based restricted stock activity:
| Number of Shares |  | Weighted Average Grant Date Fair Value
Restricted shares outstanding at December 31, 2017 | 160,724 |  |  | $ | 44.72 |
Awarded and issued (1) | 77,456 |  |  | 40.81 |
Vested (2) | (41,160) |  |  | 45.61 |
Forfeited (3) | (16,926) |  |  | 45.24 |
Restricted shares outstanding at December 31, 2018 | 180,094 |  |  | 43.34 |
Awarded and issued (1) | 87,344 |  |  | 39.42 |
Vested (2) | (45,901) |  |  | 43.68 |
Forfeited (3) | (12,689) |  |  | 43.58 |
Restricted shares outstanding at December 31, 2019 | 208,848 |  |  | 42.22 |
Awarded and issued (1) | 66,188 |  |  | 38.31 |
Forfeited (3) | (49,852) |  |  | 51.93 |
Restricted shares outstanding at December 31, 2020 | 225,184 |  |  | $ | 39.53 |
__________ (1)The fair value at grant date of total return-based restricted stock issued during the years ended December 31, 2020, 2019 and 2018 was $2.5 million, $3.4 million and $3.2 million, respectively, at target. (2)The vesting date fair value of total return-based restricted stock that vested during the years ended December 31, 2019 and 2018 was $2.1 million and $1.8 million, respectively, based on the performance of the specific plans. Vested shares include those shares surrendered by employees to satisfy tax withholding obligations in connection with such vesting. There were no vested shares of total return-based restricted stock during the year ended December 31, 2020. (3)The 2020, 2019 and 2018 amounts include 46,852, 9,521 and 13,707 shares, respectively, that were forfeited at the end of the applicable measurement period because the applicable total return did not meet targeted levels.

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- Definition Schedule of non-qualified deferred compensation liability. Dislcosure represents the portion of the balance sheet assertion valued at fair value by the entity in connection with the fair value disclosures required in the footnotes to the financial statements. This item represents currently earned compensation under compensation arrangements that is not actually paid until a later date. + References No definition available. + Details
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