STOCK INCENTIVE PLANS - Stock Options Units Activity (Detail) - $ / shares	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Shares, options outstanding at beginning of period	722,650	892,532
Shares, assumed from acquisitions	0	207,645
Shares, exercised	(214,781)	(163,455)
Shares, forfeited/expired	(4,834)	(56,687)
Shares, options outstanding and exercisable at end of period	503,035	880,035
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted average exercise price, options outstanding at beginning of period (in USD per share)	$ 7.96	$ 8.95
Weighted average exercise price, assumed from acquisitions (in USD per share)	0.00	8.92
Weighted average exercise price, exercised (in USD per share)	7.91	9.41
Weighted average exercise price, forfeited/expired (in USD per share)	11.65	11.16
Weighted average exercise price, options outstanding and exercisable at end of period (in USD per share)	$ 7.97	$ 8.72

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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The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average price at which grantees could acquire or could have acquired the underlying shares with respect to any other type of change in shares reserved for issuance.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Number of share options (or share units) exercised during the current period.

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