CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Revenues:
Transactional and maintenance		$ 161,249	$ 150,743	$ 314,909	$ 297,815
Professional services		41,284	39,342	84,827	73,494
License		25,845	16,593	48,242	35,445
Total revenues		228,378	206,678	447,978	406,754
Operating expenses:
Cost of revenues	[1]	72,131	62,298	142,128	124,491
Research and development		26,663	24,848	52,805	49,479
Selling, general and administrative	[1]	86,231	77,501	171,445	156,339
Amortization of intangible assets	[1]	3,312	3,507	6,632	7,087
Total operating expenses		188,337	168,154	373,010	337,396
Operating income		40,041	38,524	74,968	69,358
Interest expense, net		(6,578)	(6,815)	(12,750)	(13,539)
Other income (expense), net		(327)	435	(427)	101
Income before income taxes		33,136	32,144	61,791	55,920
Provision for income taxes		8,052	9,028	(1,194)	13,563
Net income		25,084	23,116	62,985	42,357
Other comprehensive income (loss):
Foreign currency translation adjustments		6,089	(905)	(8,258)	(7,024)
Comprehensive income		$ 31,173	$ 22,211	$ 54,727	$ 35,333
Earnings per share:
Basic (in dollars per share)		$ 0.81	$ 0.74	$ 2.03	$ 1.36
Diluted (in dollars per share)		$ 0.78	$ 0.72	$ 1.94	$ 1.31
Shares used in computing earnings per share:
Basic (in shares)		31,017	31,268	31,003	31,226
Diluted (in shares)		32,260	32,262	32,398	32,349

[1] Cost of revenues and selling, general and administrative expenses exclude the amortization of intangible assets. See Note 4.