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Capital Transactions - Narrative (Details) - USD ($) |  |  |  | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
May 05, 2021 | Apr. 05, 2021 | Mar. 10, 2021 | Sep. 30, 2021 | Mar. 31, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2015 | Dec. 31, 2020 | Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common stock, dividends (in dollars per share) |  | $ 1.00 |  |  |  |  |  |  |  |  |
Dividends, common stock, cash |  | $ 19,900,000 |  |  | $ 19,858,000 |  |  |  |  |  |
Stock repurchase program, authorized amount |  |  | $ 15,000,000 |  |  |  |  |  |  |  |
Stock repurchase program, remaining authorized repurchase amount |  |  |  | $ 9,000,000 |  |  | $ 9,000,000 |  |  |  |
2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares authorized under the plan (in shares) |  |  |  |  |  |  |  |  |  |  | 1,500,000
Additional number of shares authorized under the plan (in shares) | 2,000,000 |  |  |  |  |  |  |  | 1,500,000 |  |
Stock options |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  | $ 0 | 0 |  | $ 0 | 0 | $ 0 |  |  |
Unrecognized share-based compensation expense |  |  |  | $ 0 |  |  | $ 0 |  |  | $ 0 |
Stock dividends (in shares) |  |  | 4,300 |  |  |  |  |  |  |  |
Options outstanding (in shares) |  |  |  | 173,000 |  |  | 173,000 |  |  | 226,000 |
Aggregate intrinsic value, outstanding |  |  |  | $ 500,000 |  |  | $ 500,000 |  |  | $ 700,000 |
Exercised (in shares) |  |  |  |  |  |  | 53,000 | 41,000 |  |  |
Exercised (in dollars per share) |  |  |  |  |  |  | $ 12.00 | $ 7.92 |  |  |
Aggregate intrinsic values of options exercised |  |  |  |  |  |  | $ 400,000 | $ 100,000 |  |  |
Tax benefit from the exercise of stock options |  |  |  |  |  |  | $ 200,000 | 100,000 |  |  |
Weighted-average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 0 |  |  |  |
Time-based stock options | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 48 months |  |  |  |
Performance based stock options operating income margins |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating income margin, one (as a percent) |  |  |  |  |  |  | 6.00% |  |  |  |
Operating income margin, two (as a percent) |  |  |  |  |  |  | 8.00% |  |  |  |
Operating income margin, three (as a percent) |  |  |  |  |  |  | 10.00% |  |  |  |
Unvested stock options outstanding (in shares) |  |  |  | 0 |  |  | 0 |  |  | 0 |
Performance based stock options operating income margins | Minimum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award performance period |  |  |  |  |  |  | 1 year |  |  |  |
Performance based stock options operating income margins | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award performance period |  |  |  |  |  |  | 1 year 3 months |  |  |  |
RSUs |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  | $ 0 | $ 600,000 |  | 500,000 | $ 1,600,000 | $ 1,400,000 |  |  |
Unrecognized share-based compensation expense |  |  |  | $ 2,000,000 |  |  | $ 2,000,000 |  |  | $ 1,300,000 |
Discount for lack of marketability |  |  |  |  |  |  | 12.70% |  |  |  |
Award performance period |  |  |  |  |  |  | 3 years |  |  |  |
Weighted-average period over which the remaining compensation cost is expected to be recognized |  |  |  |  |  |  | 9 months 18 days |  |  |  |
Minimum withholding requirements (in shares) |  |  |  |  |  |  | 150,000 | 41,000 |  |  |
RSUs | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  | 306,000 |  |  |  |
RSUs | Minimum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Expected volatility (as a percent) |  |  |  |  |  |  | 50.00% |  |  |  |
Risk-free interest rate (as a percent) |  |  |  |  |  |  | 0.30% |  |  |  |
RSUs | Minimum | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 12 months |  |  |  |
RSUs | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Expected volatility (as a percent) |  |  |  |  |  |  | 54.70% |  |  |  |
Risk-free interest rate (as a percent) |  |  |  |  |  |  | 2.90% |  |  |  |
RSUs | Maximum | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 36 months |  |  |  |
RSUs | Director | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restriction period for issuance of shares |  |  |  |  |  |  | 2 years |  |  |  |
Nonvested subject to restriction period (in shares) |  |  |  | 94,000 |  |  | 94,000 |  |  | 82,000 |
Time-Based Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  | 22,000 |  |  |  |  |  |  |  |
Time-Based Restricted Stock Units (RSUs) | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 3 years |  |  |  |
Weighted-average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 18.05 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  | $ 300,000 |  | $ 500,000 | $ 1,200,000 | $ 800,000 |  |  |
Granted (in shares) |  |  | 26,200 |  |  |  |  |  |  |  |
Performance-Based Restricted Stock Units (RSUs) | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Weighted-average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 13.87 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share based compensation potential compensation expense to be recognized |  |  |  | $ 1,800,000 |  |  | $ 1,800,000 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) | Net Sales and Operating Income Targets | 2012 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 3 years |  |  |  |

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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 estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + 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)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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