Condensed Consolidated Statement Of Changes In Equity - USD ($) $ in Thousands		Total		Common And Treasury Stock [Member]	Treasury Stock [Member]	Number Of Shares, Net Of Treasury [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Parent [Member]	Noncontrolling Interest [Member]
Balance, Number of Shares at Jun. 30, 2018				81,577,217	(24,891,292)	56,685,925
Balance at Jun. 30, 2018		$ 736,897		$ 80	$ (286,951)		$ 276,201	$ 836,194	$ (184,538)	$ 640,986	$ 95,911
Redeemable Common Stock, Balance at Jun. 30, 2018		107,672
Restricted stock granted, shares				148,000		148,000
Stock-based compensation charge (Note 14)		1,185					1,185			1,185
Stock based-compensation charge related to equity-accounted investment (Note 7)		77					77			77
Dividends paid to non-controlling interest		(2,937)									(2,937)
Net (loss) income		(66,073)						(69,140)		(69,140)	3,067
Other comprehensive loss (Note 13)		$ (18,245)							(13,836)	(13,836)	(4,409)
Balance, Number of Shares at Dec. 31, 2018		56,833,925		81,725,217	(24,891,292)	56,833,925
Balance at Dec. 31, 2018		$ 650,904		$ 80	$ (286,951)		277,463	767,054	(198,374)	559,272	91,632
Redeemable Common Stock, Balance at Dec. 31, 2018		107,672
Balance, Number of Shares at Sep. 30, 2018				81,725,217	(24,891,292)	56,833,925
Balance at Sep. 30, 2018		722,836		$ 80	$ (286,951)		276,865	830,995	(189,630)	631,359	91,477
Redeemable Common Stock, Balance at Sep. 30, 2018		107,672
Stock-based compensation charge (Note 14)		598					598			598
Dividends paid to non-controlling interest		(1,208)									(1,208)
Net (loss) income		(60,969)						(63,941)		(63,941)	2,972
Other comprehensive loss (Note 13)		$ (10,353)							(8,744)	(8,744)	(1,609)
Balance, Number of Shares at Dec. 31, 2018		56,833,925		81,725,217	(24,891,292)	56,833,925
Balance at Dec. 31, 2018		$ 650,904		$ 80	$ (286,951)		277,463	767,054	(198,374)	559,272	91,632
Redeemable Common Stock, Balance at Dec. 31, 2018		107,672
Balance, Number of Shares at Jun. 30, 2019				81,459,717	(24,891,292)	56,568,425
Balance at Jun. 30, 2019		319,429	[1]	$ 80	$ (286,951)		276,997	528,576	(199,273)	319,429	0
Redeemable Common Stock, Balance at Jun. 30, 2019	[1]	107,672
Stock-based compensation charge (Note 14)		823					823			823
Stock based-compensation charge related to equity-accounted investment (Note 7)		71					71			71
Net (loss) income		(4,597)						(4,597)		(4,597)
Other comprehensive loss (Note 13)		$ 4,834							4,834	4,834
Balance, Number of Shares at Dec. 31, 2019		56,568,425		81,459,717	(24,891,292)	56,568,425
Balance at Dec. 31, 2019		$ 320,560		$ 80	$ (286,951)		277,891	523,979	(194,439)	320,560	0
Redeemable Common Stock, Balance at Dec. 31, 2019		107,672
Balance, Number of Shares at Sep. 30, 2019				81,459,717	(24,891,292)	56,568,425
Balance at Sep. 30, 2019		300,128		$ 80	$ (286,951)		277,455	524,184	(214,640)	300,128	0
Redeemable Common Stock, Balance at Sep. 30, 2019		107,672
Stock-based compensation charge (Note 14)		436					436			436
Net (loss) income		(205)						(205)		(205)
Other comprehensive loss (Note 13)		$ 20,201							20,201	20,201	0
Balance, Number of Shares at Dec. 31, 2019		56,568,425		81,459,717	(24,891,292)	56,568,425
Balance at Dec. 31, 2019		$ 320,560		$ 80	$ (286,951)		$ 277,891	$ 523,979	$ (194,439)	$ 320,560	$ 0
Redeemable Common Stock, Balance at Dec. 31, 2019		$ 107,672

[1] Derived from audited financial statements.