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Share-Based Compensation - Additional Information (Detail) |  | 3 Months Ended | 12 Months Ended
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Aug. 17, 2017 USD ($) Member shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($) $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Maximum number of shares authorized to issued as options | shares |  | 1,900,000 | 1,900,000 |  |
Share-based compensation expense | $ |  |  | $ 5,496,000 | $ 3,935,000 | $ 4,039,000
Tax benefit for share-based compensation cost | $ |  |  | 1,600,000 | $ 600,000 | $ 600,000
Unrecognized compensation costs related to unvested awards | $ |  | $ 4,600,000 | $ 4,600,000 |  |
Unrecognized compensation costs, period for recognition |  |  | 2 years |  |
Term life of options |  |  | 10 years |  |
Stock awards granted vesting period | 2 years |  | 3 years |  |
Number of options granted | shares |  |  | 126,000 | 167,000 | 54,100
Weighted average grant date fair value of the options granted | $ / shares |  |  | $ 11.84 | $ 5.02 | $ 12.61
Cash proceeds from the exercise of options | $ |  |  | $ 3,110,000 | $ 2,832,000 | $ 2,041,000
Total intrinsic value of options exercised | $ |  |  | 3,784,000 | 2,900,000 | 2,600,000
Tax benefit recognized from stock option exercises | $ |  |  | 200,000 |  | 100,000
Options awards vested | shares | 58,094 |  |  |  |
Selling, General and Administrative Expense [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based compensation expense | $ |  |  | $ 1,000,000 | $ 500,000 | $ 700,000
Discontinued Operations, Disposed of by Sale [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Incremental compensation costs | $ | $ 800,000 |  |  |  |
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock awards granted vesting period |  |  | 3 years |  |
Stock units issued | shares |  |  | 85,000 | 152,510 | 114,475
Fair value assumptions, exercise price | $ / shares |  | $ 24.29 | $ 24.29 |  |
Options awards vested | shares |  |  | 2,100,000 | 2,600,000 | 1,200,000
Restricted stock awards accelerated | shares | 25,564 |  |  |  |
TSR Awards [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock units issued | shares |  |  | 46,000 |  |
Options awards vested | shares |  |  | 1,200,000 |  |
Percentage of shares issuable based on threshold performance |  |  | 50.00% | 50.00% | 50.00%
Percentage of shares issuable based on target performance |  |  | 100.00% | 100.00% | 100.00%
Percentage of shares issuable based on maximum performance |  |  | 150.00% | 150.00% | 150.00%
ROIC Awards [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock units issued | shares |  |  | 53,000 |  |
Options awards vested | shares |  |  | 900,000 |  |
Percentage of shares issuable based on threshold performance |  |  | 35.00% | 35.00% | 35.00%
Percentage of shares issuable based on target performance |  |  | 100.00% | 100.00% | 100.00%
Percentage of shares issuable based on maximum performance |  |  | 150.00% | 150.00% | 150.00%
ROIC Awards [Member] | Selling, General and Administrative Expense [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based compensation expense | $ |  | $ 400,000 |  |  |
Officers and Key Employees [Member] | Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock awards granted vesting period |  |  | 3 years |  |
Non-executive Directors [Member] | Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock awards granted vesting period |  |  | 1 year |  |
Executive Management [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of members who got vesting of share-based awards | Member | 19 |  |  |  |
Maximum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Tax benefit recognized from stock option exercises | $ |  |  |  | $ 100,000 |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Net number of share options (or share units) granted during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition An excess of the fair value of the modified award over the fair value of the award immediately before the modification. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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