Quarterly report pursuant to Section 13 or 15(d)

Share-Based Compensation - Schedule of Restricted Stock Awards (Detail)

v3.19.1
Share-Based Compensation - Schedule of Restricted Stock Awards (Detail) - Restricted stock awards
3 Months Ended
Mar. 31, 2019
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]  
Number of Shares, Restricted stock at beginning of period (shares) | shares 304,595
Number of Shares, Restricted stock granted (shares) | shares 1,670
Number of Shares, Restricted stock vested (shares) | shares (69,170)
Number of Shares, Restricted stock forfeited (shares) | shares (50,801)
Number of Shares, Restricted stock at end of period (shares) | shares 186,294
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]  
Weighted-Average Grant Date Fair Value Per Share, Restricted stock at beginning of period (in usd per share) | $ / shares $ 21.98
Weighted-Average Grant Date Fair Value Per Share, Restricted stock granted (in usd per share) | $ / shares 19.84
Weighted-Average Grant Date Fair Value Per Share, Restricted stock vested (in usd per share) | $ / shares 27.99
Weighted-Average Grant Date Fair Value Per Share, Restricted stock forfeited (in usd per share) | $ / shares 12.10
Weighted-Average Grant Date Fair Value Per Share, Restricted stock at end of period (in usd per share) | $ / shares $ 22.31