STOCK-BASED COMPENSATION - NON-OPTIONS (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2022	Jun. 30, 2021	Jun. 30, 2020
Other stock-based compensation
Contractual term of awards		10 years
Minimum
Other stock-based compensation
Continuous service period for awards to vest		1 year
Maximum
Other stock-based compensation
Continuous service period for awards to vest		3 years
Restricted stock
Non-vested other than stock options, number of shares
Outstanding at the beginning of the period (in shares)		128,058
Granted (in shares)		28,218
Forfeited (in shares)		(3,270)
Vested (in shares)		(32,464)
Outstanding at the end of the period (in shares)	128,058	120,542
Other than stock options, weighted-average grant date fair value
Non-vested at the beginning of the period (in dollars per share)		$ 111.03
Granted (in dollars per share)		126.69
Forfeited (in dollars per share)		121.06
Vested (in dollars per share)		102.38
Non-vested at the end of the period (in dollars per share)	$ 111.03	$ 116.76
Restricted stock | Officers and Certain Employees
Non-vested other than stock options, number of shares
Granted (in shares)		24,090
Other stock-based compensation
Vesting period	3 years	3 years	3 years	3 years
Holding period of awards as a vesting condition			2 years	2 years
Vesting (as a percent)			33.00%	33.00%
Restricted stock | Non Executive Directors
Non-vested other than stock options, number of shares
Granted (in shares)		4,128
Other stock-based compensation
Vesting period		1 year
Vesting (as a percent)		50.00%
Percentage of shares granted to non-executive directors, vesting one year after date of grant		50.00%
Performance stock
Non-vested other than stock options, number of shares
Outstanding at the beginning of the period (in shares)		167,378
Granted (in shares)		39,380
Forfeited (in shares)		(6,480)
Vested (in shares)		(6,830)
Non-attainment (in shares)		(27,007)
Outstanding at the end of the period (in shares)	167,378	166,441
Other than stock options, weighted-average grant date fair value
Non-vested at the beginning of the period (in dollars per share)		$ 108.75
Granted (in dollars per share)		148.89
Forfeited (in dollars per share)		118.62
Vested (in dollars per share)		107.77
Non-attainment (in dollars per share)		83.16
Non-vested at the end of the period (in dollars per share)	$ 108.75	$ 122.05
Other stock-based compensation
Earn out basis if no goals are met (as a percent)			0.00%	0.00%
Earn out basis if some goals are met (as a percent)			100.00%	100.00%
Earn out basis if all goals are met (as a percent)		200.00%	200.00%	200.00%
Performance stock | Vesting upon achievement of annual growth in Net GEOs
Other stock-based compensation
Vesting (as a percent)			50.00%	50.00%
Gold Equivalent Ounces Shares
Other stock-based compensation
Contractual term of awards			5 years	5 years
Total Shareholder Return Shares
Other stock-based compensation
Contractual term of awards	3 years	3 years	3 years	3 years
Continuous service period for awards to vest	3 years	3 years	3 years	3 years
Earn out basis if no goals are met (as a percent)	0.00%	0.00%
Earn out basis if some goals are met (as a percent)	100.00%	100.00%
Earn out basis if all goals are met (as a percent)	200.00%	200.00%
Stock appreciation rights
Non-vested other than stock options, number of shares
Outstanding at the beginning of the period (in shares)		184,137
Granted (in shares)	0	0
Forfeited (in shares)		(2,110)
Exercised (in shares)	0	(7,121)
Outstanding at the end of the period (in shares)	184,137	174,906
Exercisable at the end of the period (in shares)		154,602
Other than stock options, weighted-average grant date fair value
Non-vested at the beginning of the period (in dollars per share)		$ 111.15
Exercised (in dollars per share)		90.41
Forfeited (in dollars per share)		139.84
Non-vested at the end of the period (in dollars per share)	$ 111.15	111.65
Exercisable at the end of the period (in dollars per share)		$ 107.95
Other than stock options, weighted-average remaining contractual life (in years)
Outstanding at the end of the period		6 years 2 months 12 days
Exercisable at the end of the period		6 years
Aggregate Intrinsic Value
Intrinsic value on outstanding shares		$ 2,396
Intrinsic value on exercisable shares		2,396
Other stock-based compensation
Fair value granted (in dollars per share)			$ 40.92	$ 32.33
Total intrinsic value		$ 200	$ 100	$ 4,600