Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
Revenues:
System and software	$ 198,605	$ 168,699	$ 439,064	$ 486,831
Service and support	123,911	121,817	365,435	356,890
Total revenues	322,516	290,516	804,499	843,721
Cost of revenues:
System and software	13,713	9,759	37,375	36,432
Service and support	35,649	35,286	100,910	100,275
Amortization of purchased technology	1,828	1,844	5,400	5,496
Total cost of revenues	51,190	46,889	143,685	142,203
Gross profit	271,326	243,627	660,814	701,518
Operating expenses:
Research and development	101,023	99,669	285,561	278,237
Marketing and selling	91,646	93,165	259,816	262,857
General and administration	20,015	19,665	56,777	56,298
Equity in earnings of Frontline	(634)	(1,755)	(2,311)	(3,976)
Amortization of intangible assets	1,462	2,364	4,536	6,817
Special charges	1,500	4,831	5,936	43,994
Total operating expenses	215,012	217,939	610,315	644,227
Operating income:	56,314	25,688	50,499	57,291
Other income	268	320	1,795	849
Interest expense	(5,143)	(4,915)	(14,971)	(14,381)
Income before income tax	51,439	21,093	37,323	43,759
Income tax expense	9,677	7,204	5,560	9,763
Net income	41,762	13,889	31,763	33,996
Less: Loss attributable to noncontrolling interest	0	(790)	0	(2,010)
Net income attributable to Mentor Graphics shareholders	$ 41,762	$ 14,679	$ 31,763	$ 36,006
Net income per share:
Basic	$ 0.38	$ 0.13	$ 0.29	$ 0.31
Diluted	$ 0.37	$ 0.12	$ 0.29	$ 0.30
Weighted average number of shares outstanding:
Basic	108,887	117,759	108,442	116,787
Diluted	114,112	120,141	110,931	121,963
Cash dividends declared per common share	$ 0.055	$ 0.055	$ 0.165	$ 0.165