Other Assets Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 552,853
Goodwill, ending balance	552,465	$ 552,853
Bank Systems and Services [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	423,282	420,795
Goodwill, acquired during the year	0	6,099
Goodwill, written off related to sale	(388)	(3,612)
Goodwill, ending balance	422,894	423,282
Credit Union Systems and Services [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	129,571	129,571
Goodwill, acquired during the year	0	0
Goodwill, ending balance	$ 129,571	129,571
Business Acquisition, Bayside Business Solutions [Member] \| Bank Systems and Services [Member]
Goodwill [Roll Forward]
Goodwill, acquired during the year		$ 6,099

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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