Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended |
Sep. 30, 2017 | Oct. 01, 2016 | Sep. 30, 2017 | Oct. 01, 2016 |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | |
Stock split, conversion ratio | | | | 2 | |
Share-based compensation arrangement by share-based payment award, percentage of outstanding stock maximum | | | | 5.00% | |
Share-based compensation arrangement by share-based payment award, percentage of outstanding and available for grant, maximum | | | | 10.00% | |
Compensation expense, share-based payment plans | | $ 847 | $ 731 | $ 3,295 | $ 2,055 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] | | | | | |
Volatility rate | | | | 10.30% | 10.60% |
Risk-free interest rate | | | | 2.20% | 1.80% |
Expected dividend yield | | | | 0.70% | 0.70% |
Expected life of awards (years) | | | | 8 years 10 months 24 days | 9 years 6 months |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] | | | | | |
Outstanding, beginning balance | [1] | | | 1,599,296 | |
Granted | [1] | | | 148,500 | |
Exercised | [1] | | | (87,507) | |
Forfeited | [1] | | | (81,074) | |
Outstanding, ending balance | [1] | 1,579,215 | | 1,579,215 | |
Exercisable, ending balance | [1] | 851,215 | | 851,215 | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] | | | | | |
Outstanding, weighted average exercise price, beginning balance | [1] | | | $ 12.49 | |
Granted, weighted average exercise price | [1] | | | 17.6 | |
Exercised, weighted average exercise price | [1] | | | 10.59 | |
Forfeited, weighted average exercise price | [1] | | | 13.34 | |
Outstanding, weighted average exercise price, ending balance | [1] | $ 13.03 | | 13.03 | |
Exercisable, weighted average exercise price, ending balance | [1] | $ 11.22 | | $ 11.22 | |
Exercisable, weighted average remaining contractual life (years) | | | | 5 years 1 month 17 days | |
Outstanding, aggregate intrinsic value | | $ 7,217 | | $ 7,217 | |
Exercisable, aggregate intrinsic value | | 5,422 | | 5,422 | |
Outstanding, unrecognized compensation cost | | $ 1,707 | | $ 1,707 | |
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition | | | | 2 years 7 months 28 days | |
Employee stock purchase plan [Domain] | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | |
Compensation expense, share-based payment plans | | | | $ 670 | $ 547 |
Employee stock purchase plan, service period | | | | 1 year | |
Employee stock purchase plan, percentage of market price, purchase date | | | | 85.00% | |
Employee stock purchase plan, discount from market price, purchase date | | | | 15.00% | |
Stock option plans [Member] | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | |
Compensation expense, share-based payment plans | | | | $ 532 | 426 |
Stock options awarded, term (years) | | | | 10 years | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] | | | | | |
Outstanding, weighted average remaining contractual life (years) | | | | 6 years 5 months 9 days | |
Stock-settled stock appreciation rights (SSARs) [Member] | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | |
Compensation expense, share-based payment plans | | | | $ 931 | 436 |
Share-based compensation arrangement by share-based payment award, award vesting period | | | | 5 years | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | | | | | |
Unvested, beginning balance | [1] | | | 743,662 | |
Granted | [1] | | | 152,000 | |
Forfeited | [1] | | | 0 | |
Vested | [1] | | | (411,502) | |
Unvested, ending balance | [1] | 484,160 | | 484,160 | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] | | | | | |
Unvested, weighted average award date value, beginning balance | [1] | | | $ 2.75 | |
Granted, weighted average award date value | [1] | | | 3.57 | |
Forfeited, weighted average award date value | [1] | | | 0 | |
Vested, weighted average award date value | [1] | | | 2.74 | |
Unvested, weighted average award date value, ending balance | [1] | $ 3.01 | | $ 3.01 | |
Weighted average remaining contractual life (years) | | | | 2 years 6 months 15 days | |
Unrecognized compensation cost | | $ 1,127 | | $ 1,127 | |
Aggregate intrinsic value | | $ 8,521 | | $ 8,521 | |
Employee SSARs [Member] | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | | | | | |
Unvested, ending balance | [1] | 484,160 | | 484,160 | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] | | | | | |
Unvested, weighted average award date value, ending balance | [1] | $ 3.01 | | $ 3.01 | |
Weighted average remaining contractual life (years) | | | | 2 years 6 months 15 days | |
Unrecognized compensation cost | | $ 1,127 | | $ 1,127 | |
Aggregate intrinsic value | | $ 8,521 | | 8,521 | |
Restricted stock units (RSUs) [Member] | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | |
Compensation expense, share-based payment plans | | | | $ 1,162 | $ 646 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | | | | | |
Unvested, beginning balance | [1] | | | 304,958 | |
Granted | [1] | | | 80,350 | |
Forfeited | [1] | | | 0 | |
Vested | [1] | | | (91,022) | |
Unvested, ending balance | [1] | 294,286 | | 294,286 | |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] | | | | | |
Unvested, weighted average award date value, beginning balance | [1] | | | $ 13.22 | |
Granted, weighted average award date value | [1] | | | 17.01 | |
Forfeited, weighted average award date value | [1] | | | 0 | |
Vested, weighted average award date value | [1] | | | 12.68 | |
Unvested, weighted average award date value, ending balance | [1] | $ 14.42 | | $ 14.42 | |
Weighted average remaining contractual life (years) | | | | 2 years 5 months 27 days | |
Unrecognized compensation cost | | $ 2,323 | | $ 2,323 | |
Aggregate intrinsic value | | $ 5,179 | | $ 5,179 | |
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[1] | Adjusted for two-for-one stock split | |