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STOCK-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 29, 2018 | Dec. 30, 2017 | Dec. 31, 2016
Stock Based Compensation |  |  |
Shares of common stock available for issuance | 1,419,000 |  |
Number of Shares |  |  |
Exercised (in shares) | (63,717) | (284,574) | (109,893)
Employee Stock Option [Member] |  |  |
Stock Based Compensation |  |  |
Compensation expense (included in selling, general and administrative expenses) | $ 4,064 | $ 5,137 | $ 5,782
Tax benefits associated with compensation expense | $ 1,016 | $ 1,952 | $ 2,197
Weighted average period over which unrecognized stock option compensation cost would be recognized | 2 years 5 months 9 days |  |
Unrecognized stock option compensation expense | $ 5,940 |  |
Assumptions used in estimating fair value of each option grant |  |  |
Expected volatility (as a percent) | 33.39% | 33.76% | 33.88%
Risk-free interest rate (as a percent) | 2.67% | 2.12% | 1.83%
Expected life from vesting date | 3 years | 3 years | 3 years
Dividend yield (as a percent) | 1.07% | 1.17% | 1.13%
Number of Shares |  |  |
Balance at the beginning of the period (in shares) | 570,622 | 793,173 | 849,609
Granted (in shares) | 105,135 | 67,965 | 85,092
Exercised (in shares) | (63,717) | (284,574) | (109,893)
Forfeited (in shares) | (33,627) | (5,942) | (31,635)
Balance at the end of the period (in shares) | 578,413 | 570,622 | 793,173
Options vested or expected to vest (in shares) | 565,952 | 558,114 | 774,139
Options exercisable (in shares) | 405,128 | 351,794 | 469,844
Weighted Average Exercise Price |  |  |
Balance at the beginning of the period (in dollars per share) | $ 128,340 | $ 122,770 | $ 117,420
Granted (in dollars per share) | 112,080 | 164,350 | 151,370
Exercised (in dollars per share) | (106,260) | (121,920) | 101,690
Forfeited (in dollars per share) | (129,520) | (104,260) | 129,360
Balance at the end of the period (in dollars per share) | 127,740 | 128,340 | 122,770
Options vested or expected to vest (in dollars per share) | 127,840 | 128,000 | 124,180
Options exercisable (in dollars per share) | $ 126,610 | $ 123,900 | $ 123,750
Weighted Average Remaining Contractual Term |  |  |
Options outstanding | 4 years 4 months 5 days | 4 years 7 months 28 days | 4 years 9 months 12 days
Options vested or expected to vest | 4 years 3 months 20 days | 4 years 7 months 16 days | 4 years 9 months 1 day
Options exercisable | 3 years 5 months 18 days | 3 years 11 months 8 days | 3 years 11 months 16 days
Aggregate Intrinsic Value |  |  |
Options outstanding | $ 909 | $ 21,806 | $ 16,640
Options vested or expected to vest | 909 | 21,517 | 16,200
Options exercisable | $ 909 | $ 15,005 | $ 9,056
Other option disclosures |  |  |
Weighted average per share fair value of option granted | $ 30.48 | $ 43.68 | $ 40.00
Employee Stock Option [Member] | Minimum |  |  |
Stock Based Compensation |  |  |
Vesting period of options | 3 years |  |

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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=109197908&loc=d3e5070-113901 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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