Consolidated Statement Of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive (Loss) Income [Member]
Balance at Jun. 30, 2018	$ 1,737,049	$ 1,084	$ 1,148,196	$ 878,516	$ (106,507)	$ (184,240)
Balance (shares) at Jun. 30, 2018		108,422			4,470
Increase (Decrease) in Stockholders' Equity
Net loss	(37,425)			(37,425)
Other comprehensive income (loss)	(13,519)					(13,519)
Issuance of common stock pursuant to stock-based compensation plans	0	$ 1	(1)
Issuance of common stock pursuant to stock-based compensation plans (shares)		85
Shares withheld for payment of employee payroll taxes due on shares issued under stock-based compensation plans	(979)				$ (979)
Shares withheld for payment of employee payroll taxes due on shares issued under stock based compensation plans (shares)					35
Stock-based compensation expense	135		135
Balance at Sep. 30, 2018	1,685,424	$ 1,085	1,148,330	840,906	$ (107,486)	(197,411)
Balance (shares) at Sep. 30, 2018		108,507			4,505
Balance at Jun. 30, 2018	1,737,049	$ 1,084	1,148,196	878,516	$ (106,507)	(184,240)
Balance (shares) at Jun. 30, 2018		108,422			4,470
Increase (Decrease) in Stockholders' Equity
Net loss	(103,926)
Balance at Dec. 31, 2018	1,590,943	$ 1,087	1,150,239	774,405	$ (109,429)	(225,359)
Balance (shares) at Dec. 31, 2018		108,691			4,584
Balance at Sep. 30, 2018	1,685,424	$ 1,085	1,148,330	840,906	$ (107,486)	(197,411)
Balance (shares) at Sep. 30, 2018		108,507			4,505
Increase (Decrease) in Stockholders' Equity
Net loss	(66,501)			(66,501)
Other comprehensive income (loss)	(27,948)					(27,948)
Issuance of common stock pursuant to stock-based compensation plans	0	$ 2	(2)
Issuance of common stock pursuant to stock-based compensation plans (shares)		184
Shares withheld for payment of employee payroll taxes due on shares issued under stock-based compensation plans	(1,943)				$ (1,943)
Shares withheld for payment of employee payroll taxes due on shares issued under stock based compensation plans (shares)					79
Stock-based compensation expense	1,911		1,911
Balance at Dec. 31, 2018	1,590,943	$ 1,087	1,150,239	774,405	$ (109,429)	(225,359)
Balance (shares) at Dec. 31, 2018		108,691			4,584
Balance at Jun. 30, 2019	$ 1,519,319	$ 1,088	1,158,257	695,017	$ (110,039)	(225,004)
Balance (shares) at Jun. 30, 2019	108,833	108,833			4,614
Increase (Decrease) in Stockholders' Equity
Net loss	$ (107,021)			(107,021)
Other comprehensive income (loss)	56,110					56,110
Issuance of common stock pursuant to stock-based compensation plans	0	$ 1	(1)
Issuance of common stock pursuant to stock-based compensation plans (shares)		40
Shares withheld for payment of employee payroll taxes due on shares issued under stock-based compensation plans	(312)				$ (312)
Shares withheld for payment of employee payroll taxes due on shares issued under stock based compensation plans (shares)					17
Stock-based compensation expense	3,281		3,281
Balance at Sep. 30, 2019	1,470,938	$ 1,089	1,161,537	587,557	$ (110,351)	(168,894)
Balance (shares) at Sep. 30, 2019		108,873			4,631
Balance at Jun. 30, 2019	$ 1,519,319	$ 1,088	1,158,257	695,017	$ (110,039)	(225,004)
Balance (shares) at Jun. 30, 2019	108,833	108,833			4,614
Increase (Decrease) in Stockholders' Equity
Net loss	$ (107,985)
Balance at Dec. 31, 2019	$ 1,521,083	$ 1,091	1,164,618	586,593	$ (111,022)	(120,197)
Balance (shares) at Dec. 31, 2019	109,019	109,019			4,658
Balance at Sep. 30, 2019	$ 1,470,938	$ 1,089	1,161,537	587,557	$ (110,351)	(168,894)
Balance (shares) at Sep. 30, 2019		108,873			4,631
Increase (Decrease) in Stockholders' Equity
Net loss	(964)			(964)
Other comprehensive income (loss)	48,697					48,697
Issuance of common stock pursuant to stock-based compensation plans	0	$ 2	(2)
Issuance of common stock pursuant to stock-based compensation plans (shares)		146
Shares withheld for payment of employee payroll taxes due on shares issued under stock-based compensation plans	(671)				$ (671)
Shares withheld for payment of employee payroll taxes due on shares issued under stock based compensation plans (shares)					27
Stock-based compensation expense	3,083		3,083
Balance at Dec. 31, 2019	$ 1,521,083	$ 1,091	$ 1,164,618	$ 586,593	$ (111,022)	$ (120,197)
Balance (shares) at Dec. 31, 2019	109,019	109,019			4,658