Recent Accounting Pronouncements Impact of Adoption of ASC 606 on Previously Reported Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
CURRENT ASSETS:
Cash and cash equivalents	$ 114,872	$ 31,440	$ 104,040	$ 114,765
Receivables, net	198,564	297,271
Income tax receivable	4,142	21,671
Prepaid expenses and other	102,425	96,141
Deferred costs	37,836	27,069
Total current assets	457,839	473,592
PROPERTY AND EQUIPMENT, net	286,497	286,850
OTHER ASSETS:
Non-current deferred costs	77,539	74,865
Computer software, net of amortization	294,836	288,172
Other non-current assets	119,500	110,299
Other intangible assets, net of amortization	36,150	38,467
Goodwill	649,929	649,929
Total other assets	1,288,766	1,276,766
Total assets	2,033,102	2,037,208
CURRENT LIABILITIES:
Accounts payable	10,477	34,510
Accrued expenses	113,074	88,764
Deferred revenues	296,675	352,431
Total current liabilities	420,226	475,705
LONG TERM LIABILITIES:
Non-current deferred revenues	21,089	17,484
Non-current deferred income tax liability	209,033	208,303
Other long-term liabilities	14,190	12,872
Total long term liabilities	244,312	238,659
Total liabilities	664,538	714,364
STOCKHOLDERS' EQUITY
Preferred stock - $1 par value; 500,000 shares authorized, none issued	0	0
Common stock - $0.01 par value; 250,000,000 shares authorized; 103,278,562 shares issued at June 30, 2018	1,034	1,033
Additional paid-in capital	454,869	464,138
Retained earnings	1,967,921	1,912,933
Less treasury stock at cost; 26,107,903 shares at June 30, 2018	(1,055,260)	(1,055,260)
Total stockholders' equity	1,368,564	1,322,844
Total liabilities and equity	2,033,102	2,037,208
Customer Relationships [Member]
OTHER ASSETS:
Customer relationships, net of amortization	$ 110,812	115,034
Accounting Standards Update 2014-09 [Member]
CURRENT ASSETS:
Cash and cash equivalents		0	0	0
Receivables, net		5,641
Income tax receivable		0
Prepaid expenses and other		11,331
Deferred costs		(11,916)
Total current assets		5,056
PROPERTY AND EQUIPMENT, net		0
OTHER ASSETS:
Non-current deferred costs		(20,675)
Computer software, net of amortization		0
Other non-current assets		2,524
Other intangible assets, net of amortization		0
Goodwill		0
Total other assets		(18,151)
Total assets		(13,095)
CURRENT LIABILITIES:
Accounts payable		0
Accrued expenses		(9,084)
Deferred revenues		(3,107)
Total current liabilities		(12,191)
LONG TERM LIABILITIES:
Non-current deferred revenues		(75,610)
Non-current deferred income tax liability		18,690
Other long-term liabilities		0
Total long term liabilities		(56,920)
Total liabilities		(69,111)
STOCKHOLDERS' EQUITY
Preferred stock - $1 par value; 500,000 shares authorized, none issued		0
Common stock - $0.01 par value; 250,000,000 shares authorized; 103,278,562 shares issued at June 30, 2018		0
Additional paid-in capital		0
Retained earnings		56,016
Less treasury stock at cost; 26,107,903 shares at June 30, 2018		0
Total stockholders' equity		56,016
Total liabilities and equity		(13,095)
Accounting Standards Update 2014-09 [Member] | Customer Relationships [Member]
OTHER ASSETS:
Customer relationships, net of amortization		0
Previously Reported [Member]
CURRENT ASSETS:
Cash and cash equivalents		31,440	$ 104,040	$ 114,765
Receivables, net		291,630
Income tax receivable		21,671
Prepaid expenses and other		84,810
Deferred costs		38,985
Total current assets		468,536
PROPERTY AND EQUIPMENT, net		286,850
OTHER ASSETS:
Non-current deferred costs		95,540
Computer software, net of amortization		288,172
Other non-current assets		107,775
Other intangible assets, net of amortization		38,467
Goodwill		649,929
Total other assets		1,294,917
Total assets		2,050,303
CURRENT LIABILITIES:
Accounts payable		34,510
Accrued expenses		97,848
Deferred revenues		355,538
Total current liabilities		487,896
LONG TERM LIABILITIES:
Non-current deferred revenues		93,094
Non-current deferred income tax liability		189,613
Other long-term liabilities		12,872
Total long term liabilities		295,579
Total liabilities		783,475
STOCKHOLDERS' EQUITY
Preferred stock - $1 par value; 500,000 shares authorized, none issued		0
Common stock - $0.01 par value; 250,000,000 shares authorized; 103,278,562 shares issued at June 30, 2018		1,033
Additional paid-in capital		464,138
Retained earnings		1,856,917
Less treasury stock at cost; 26,107,903 shares at June 30, 2018		(1,055,260)
Total stockholders' equity		1,266,828
Total liabilities and equity		2,050,303
Previously Reported [Member] | Customer Relationships [Member]
OTHER ASSETS:
Customer relationships, net of amortization		$ 115,034