Stock Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, tax benefit	$ 226	$ 121	$ 18
Option expense	$ 1,400	$ 500	$ 300
Weighted average grant date fair value of options granted (in dollars per share)	$ 13.82	$ 24.87	$ 19.36
Total intrinsic value of options exercised	$ 1,900	$ 5,400	$ 1,600
Total stock-based compensation expense	4,251	2,706	1,039
Total stock-based compensation expense included in selling, general and administrative expense	$ 4,251	$ 2,706	$ 1,039
Shares released (in shares)	23,000	0
Equity Incentive Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan approved by directors (in shares)	2,700,000
Employee Stock Options \| Equity Incentive Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Employee Stock Options \| Equity Incentive Plan 2015 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Employee Stock Options \| Equity Incentive Plan 2015 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 11,600
Granted (in shares)	29,000	225,000	79,000
Total stock-based compensation expense included in selling, general and administrative expense	$ 100
Weighted average grant date fair value (in dollars per share)	$ 30.96	$ 24.77	$ 17.08
Shares released (in shares)	112,000	13,000	31,000
Restricted stock awards cancelled (in shares)	5,000	53,000	13,000
Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 11,600
Granted (in shares)	383,000	67,000	0
Total stock-based compensation expense included in selling, general and administrative expense	$ 100
Weighted average grant date fair value (in dollars per share)	$ 13.80	$ 29.73
Restricted stock awards cancelled (in shares)	0
Restricted stock awards forfeited of canceled (in shares)	0	0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards cancelled (in shares)	4,000	38,000	12,000
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Restricted Stock And Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 2,900	$ 2,200	$ 700

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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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).

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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