Business combinations (Schedule of Finite-Lived Intangible Assets Acquired) (Details) (USD $) In Thousands, unless otherwise specified								0 Months Ended						3 Months Ended
	Mar. 31, 2014	Jun. 30, 2013	Mar. 31, 2014 Developed technology	Mar. 31, 2014 Customer relationships	Mar. 31, 2014 Maintenance contracts	Mar. 31, 2014 Trademarks	Mar. 31, 2014 Order backlog	Oct. 31, 2013 Enterasys Networks, Inc.	Oct. 31, 2013 Enterasys Networks, Inc. Developed technology	Oct. 31, 2013 Enterasys Networks, Inc. Customer relationships	Oct. 31, 2013 Enterasys Networks, Inc. Maintenance contracts	Oct. 31, 2013 Enterasys Networks, Inc. Trademarks	Oct. 31, 2013 Enterasys Networks, Inc. Order backlog	Mar. 31, 2014 Enterasys Networks, Inc. Order backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Useful Life								3 years	3 years	3 years	5 years	3 years	1 year	1 year
Amount	$ 121,806	$ 12,906	$ 45,000	$ 37,000	$ 17,000	$ 2,500	$ 7,400	$ 108,900	$ 45,000	$ 37,000	$ 17,000	$ 2,500	$ 7,400