Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
ASSETS
Cash and cash equivalents	$ 266,552	$ 280,003
Short-term marketable securities	22,356	18,408
Accounts receivable, net of allowance for doubtful accounts of $591 and $1,062 at June 30, 2018 and September 30, 2017, respectively	130,079	152,299
Prepaid expenses	46,600	49,913
Other current assets	122,625	165,933
Total current assets	588,212	666,556
Property and equipment, net	64,456	63,600
Goodwill	1,182,462	1,182,772
Acquired intangible assets, net	214,657	257,908
Long-term marketable securities	31,816	31,907
Deferred tax assets	138,958	123,166
Other assets	35,070	34,475
Total assets	2,255,631	2,360,384
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	37,773	35,160
Accrued expenses and other current liabilities	58,296	80,761
Accrued compensation and benefits	87,401	110,957
Accrued income taxes	6,683	5,735
Deferred revenue	474,957	446,296
Total current liabilities	665,110	678,909
Long-term debt	693,053	712,406
Deferred tax liabilities	5,862	17,880
Deferred revenue	8,994	12,611
Other liabilities	48,227	53,142
Total liabilities	1,421,246	1,474,948
Commitments and contingencies (Note 13)
Stockholders’ equity:
Preferred stock, $0.01 par value; 5,000 shares authorized; none issued	0	0
Common stock, $0.01 par value; 500,000 shares authorized; 115,491 and 115,333 shares issued and outstanding at June 30, 2018 and September 30, 2017, respectively	1,155	1,153
Additional paid-in capital	1,524,399	1,609,030
Accumulated deficit	(612,600)	(650,840)
Accumulated other comprehensive loss	(78,569)	(73,907)
Total stockholders’ equity	834,385	885,436
Total liabilities and stockholders’ equity	$ 2,255,631	$ 2,360,384