STOCK COMPENSATION PLANS (Details) | 3 Months Ended | | |
Mar. 31, 2017USD ($)Director$ / sharesshares | Mar. 31, 2016USD ($) | May 04, 2016$ / sharesshares | Dec. 18, 2015$ / sharesshares |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | |
Number of directors in committee | Director | 3 | | | |
Restricted Stock [Member] | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | |
Award vesting period | 1 year | | | |
Class A Stock [Member] | 2015 Equity Compensation Plan [Member] | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | |
Compensation expense | $ | $ 34,000 | $ 0 | | |
Unrecognized expense related to non-vested option shares | $ | $ 0 | | | |
Number of shares authorizes under the plan (in shares) | shares | | | 5,000 | 5,000 |
Fair market value (in dollars per share) | $ / shares | | | $ 27.70 | $ 27.38 |
Class A Stock [Member] | Stock Options [Member] | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] | | | | |
Outstanding at beginning of period, option shares (in shares) | shares | 231,755 | | | |
Granted, option shares (in shares) | shares | 0 | | | |
Exercised/vested and released, option shares (in shares) | shares | (11,500) | | | |
Expired, option shares (in shares) | shares | 0 | | | |
Outstanding at end of period, option shares (in shares) | shares | 220,255 | | | |
Exercisable/vested at end of period, option share (in shares) | shares | 220,255 | | | |
Shares of Class A Non-Voting Common Stock under option [Abstract] | | | | |
Outstanding at beginning of period, weighted average exercise price (in dollars per shares) | $ / shares | $ 19.32 | | | |
Granted, weighted average exercise price (in dollars per share) | $ / shares | 0 | | | |
Exercised/vested and released, weighted average exercise price (in dollars per shares) | $ / shares | 19.09 | | | |
Expired/cancelled, weighted average exercise price (in dollars per share) | $ / shares | 0 | | | |
Outstanding at end of period, weighted average exercise price (in dollars per shares) | $ / shares | 19.33 | | | |
Exercisable/vested at end of period, weighted average exercise price (in dollars per shares) | $ / shares | $ 19.33 | | | |
Outstanding at end of period, weighted average remaining life | 4 years 4 months 2 days | | | |
Exercisable/vested at end of period, weighted average remaining life | 4 years 4 months 2 days | | | |
Outstanding at beginning of period, aggregate intrinsic value | $ | $ 2,925,000 | | | |
Granted, aggregate intrinsic value | $ | 0 | | | |
Exercised/ vested and released, aggregate intrinsic value | $ | 158,000 | | | |
Expired/cancelled, aggregate intrinsic value | $ | 0 | | | |
Outstanding at end of period, aggregate intrinsic value | $ | 2,914,000 | | | |
Exercisable/vested at end of period, aggregate intrinsic value | $ | $ 2,914,000 | | | |
Class A Stock [Member] | Restricted Stock [Member] | | | | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] | | | | |
Outstanding at beginning of period, option shares (in shares) | shares | 5,000 | | | |
Granted, option shares (in shares) | shares | 0 | | | |
Exercised/vested and released, option shares (in shares) | shares | 0 | | | |
Expired, option shares (in shares) | shares | 0 | | | |
Outstanding at end of period, option shares (in shares) | shares | 5,000 | | | |
Exercisable/vested at end of period, option share (in shares) | shares | 0 | | | |
Shares of Class A Non-Voting Common Stock under option [Abstract] | | | | |
Outstanding at beginning of period, weighted average exercise price (in dollars per shares) | $ / shares | $ 27.70 | | | |
Granted, weighted average exercise price (in dollars per share) | $ / shares | 0 | | | |
Exercised/vested and released, weighted average exercise price (in dollars per shares) | $ / shares | 0 | | | |
Expired/cancelled, weighted average exercise price (in dollars per share) | $ / shares | 0 | | | |
Outstanding at end of period, weighted average exercise price (in dollars per shares) | $ / shares | 27.70 | | | |
Exercisable/vested at end of period, weighted average exercise price (in dollars per shares) | $ / shares | $ 0 | | | |
Class A Stock [Member] | Restricted Stock [Member] | 2015 Equity Compensation Plan [Member] | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | |
Unrecognized expense related to non-vested option shares | $ | $ 12,500 | | | |
Period over which unvested options cost will recognized | 1 month 2 days | | | |