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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option 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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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Equity Compensation Plans - Narrative (Details) - USD ($)		12 Months Ended
	Apr. 27, 2012	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense		$ 2,900,000	$ 2,100,000	$ 4,300,000
Compensation costs capitalized as part of inventory		0	0	0
Tax benefit from compensation expense		$ 200,000	$ 1,300,000	$ 4,000,000.0
Options granted (shares)		242,000
Weighted-average grant-date fair value of options (USD per share)		$ 19.35	$ 21.49	$ 17.91
Options exercised (shares)		40,147	54,316	90,897
Total intrinsic value for options exercised		$ 400,000	$ 1,400,000	$ 3,600,000
Cash received from exercise of stock option		400,000	900,000	1,300,000
Fair value of restrictions lapsed		$ 500,000	$ 3,200,000	$ 8,000,000.0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of stock awards		10 years
Options granted (shares)		242,592	245,830	99,840
Realized income tax benefit		$ 100,000	$ 300,000	$ 1,100,000
Total unrecognized compensation cost		$ 2,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term		3 years
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards		3 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards		4 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of options (USD per share)		$ 20.96	$ 25.19	$ 45.18
Total unrecognized compensation cost		$ 4,500,000
Granted (shares)		157,000
Restricted stock forfeited (shares)		150,365	8,440	14,045
Weighted average expected amortization period		2 years 4 months 24 days
Shares paid for tax withholding for share based compensation (shares)		7,122
Shares paid for tax withholding for share based compensation, value of shares withheld		$ 200,000
Time Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		97,803	71,516	22,700
Time Based Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards		2 years
Time Based Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards		4 years
Performance Based Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)		59,566	99,560	52,595
Time-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)			1,245	485
2012 Stock Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options and restricted shares authorized (shares)	1,750,000
Number of additional shares authorized (shares)	1,200,000