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SHARE BASED COMPENSATION, 401(K) PLAN AND DEFERRED COMPENSATION - Narrative (Details)				12 Months Ended
	Mar. 05, 2020 installment shares	Feb. 21, 2019	Feb. 01, 2019 shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	May 20, 2020 shares	Jan. 22, 2019 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation arrangement by share-based payment award, options, outstanding, number \| shares				300,046	334,561
Defined contribution plan, maximum annual contribution per employee, percent				100.00%
Defined contribution plan, employer discretionary contribution amount \| $				$ 500,000	$ 400,000	$ 500,000
Threshold age for qualifying retirement				57
Number of vesting installments \| installment	3
Number of shares to be issued under deferred compensation plan included in total shares outstanding \| shares				1,200,000	1,100,000
Restricted Share Rights Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share rights outstanding (in shares) \| shares				488,735	479,144
Unrecognized compensation expenses \| $				$ 1,800,000
Weighted average period over which options will be recognized				9 months 18 days
Share-based compensation expense \| $				$ 4,300,000	$ 3,900,000	3,600,000
Share-based compensation expense, capitalized \| $				$ 400,000	300,000	600,000
Granted (in shares) \| shares	183,758			295,049
Number of restricted share right will get settled for common share \| shares	1
Accumulated service period for voluntary termination	15 years
Restricted Share Rights Awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				1 year
Restricted Share Rights Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years			3 years
Restricted Performance Share Units Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Unrecognized compensation expenses \| $				$ 4,500,000
Weighted average period over which options will be recognized				1 year 6 months
Share-based compensation expense \| $				$ 3,000,000.0	4,200,000	3,900,000
Share-based compensation expense, capitalized \| $				$ 400,000	$ 600,000	1,100,000
Common shares issued for share based compensation \| shares			121,897
Dividends payable, amount per share (in usd per share) \| $ / shares								$ 0.19
Restricted Performance Share Units Plan \| Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share rights outstanding (in shares) \| shares				715,965	396,365
Granted (in shares) \| shares				319,600
Performance earning potential		200.00%
Outperformance feature measurement term		3 years		3 years
Restricted Performance Share Units Plan \| Executive Officers \| 2020 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense \| $				$ 0
Awards issuable under outperformance feature (in shares) \| shares				316,306
Restricted Performance Share Units Plan \| Executive Officers \| 2019 Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense \| $				$ 200,000
Awards issuable under outperformance feature (in shares) \| shares				233,890
Restricted Performance Share Units Plan \| Non-Officer Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share rights outstanding (in shares) \| shares	40,920						70,371
Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense \| $				$ 100,000	$ 100,000	100,000
Share-based compensation, percentage of closing price				85.00%
Maximum participant contribution, percentage of compensation				20.00%
Maximum participant contribution, dollar amount \| $				$ 50,000
Aggregate share-based awards awarded to executives \| shares				1,250,000
Stock issued during period, value, employee stock purchase plan \| $				$ 400,000	$ 500,000	$ 500,000
Share-based compensation arrangement by share-based payment award, discount from market price, purchase				15.00%