Guarantor Subsidiaries (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012	Dec. 31, 2011
Guarantor Subsidiaries [Abstract]
Ownership percentage in domestic restricted subsidiaries (in hundredths)	100.00%
Current assets:
Cash and cash equivalents (including restricted cash)	$ 44,538				$ 35,875
Accounts receivable, net	72,615				72,065
Intercompany receivables	0				0
Other current assets	37,784				35,707
Total current assets	154,937				143,647
Net property and equipment	4,695				4,964
Purchased and developed software, net	17,824				19,007
Other intangible assets, net	33,189				35,628
Goodwill	214,269				214,312
Investment in and advances to subsidiaries	0				0
Other assets	15,985				19,295
Total assets	440,899				436,853
Current liabilities:
Accounts payable	25,756				24,438
Deferred revenue	54,851				52,355
Intercompany payables	0				0
Other accrued liabilities	29,003				23,653
Total current liabilities	109,610				100,446
Notes payable	250,228				250,046
Other long-term liabilities	8,083				8,900
Total liabilities	367,921				359,392
Total shareholders' equity	72,978				77,461
Total liabilities and shareholders' equity	440,899				436,853
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	63,634		60,978
Cost of sales	28,191		24,983
Gross margin	35,443		35,995
Selling, research and development, general and administrative expenses	26,010		27,153
Acquisition-related expenses	269		362
Restructuring and other expenses	1,229		0
Depreciation and amortization	2,653		2,807
Total operating costs and expenses	30,161		30,322
Operating income	5,282		5,673
Equity in net income of subsidiaries	0		0
Other, net	(8,760)		(7,931)
Total other expense	(8,760)		(7,931)
Loss before income taxes	(3,478)		(2,258)
Income tax expense (benefit)	3,015		(395)
Net income (loss)	(6,493)		(1,863)
Cash flows from operating activities:
Net income (loss)	(6,493)		(1,863)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation, amortization and impairment	4,463		4,686
Share-based compensation	1,643		1,199
Change in contingent consideration for acquisitions	0		(297)
Amortization of note payable issuance costs and discount	736		649
Provision for doubtful accounts receivable and allowances, net of recoveries	85		524
Deferred income taxes	2,772		(95)
Unrealized loss on equity security	441
Net change in assets and liabilities (net of effects of acquisitions)	5,040		(2,632)
Net cash provided by operating activities	8,687		2,171
Cash flows from investing activities:
Cash paid for acquisitions, net of cash acquired	0		(500)
Purchases of property, equipment, and leasehold improvements	(393)		(1,743)
Intercompany advances	0		0
Net cash used in investing activities	(393)		(2,243)
Cash flows from financing activities:
Intercompany advances	0		0
Proceeds from exercise of stock options and employee stock purchase plan	396		745
Principal payments on notes payable	(5)		(27)
Principal payments on capital leases	(103)		(41)
Net cash provided by financing activities	288		677
Effect of exchange rates on cash and cash equivalents	81		(12)
Net increase in cash and cash equivalents	8,663		593
Cash and cash equivalents (net of restricted cash), beginning of period (1)	35,062	[1],[2]	38,565	[1],[3]
Cash and cash equivalents (net of restricted cash), end of period (2)	43,725	[4],[5]	39,158	[4],[6]
Restricted cash	813		707		813	707
Parent [Member]
Current assets:
Cash and cash equivalents (including restricted cash)	1,020				862
Accounts receivable, net	0				0
Intercompany receivables	1,151				1,142
Other current assets	2,671				2,668
Total current assets	4,842				4,672
Net property and equipment	113				130
Purchased and developed software, net	0				0
Other intangible assets, net	0				0
Goodwill	0				0
Investment in and advances to subsidiaries	350,642				345,364
Other assets	5,556				5,957
Total assets	361,153				356,123
Current liabilities:
Accounts payable	1,241				1,509
Deferred revenue	0				0
Intercompany payables	22,175				20,008
Other accrued liabilities	11,784				4,352
Total current liabilities	35,200				25,869
Notes payable	250,228				250,046
Other long-term liabilities	2,747				2,747
Total liabilities	288,175				278,662
Total shareholders' equity	72,978				77,461
Total liabilities and shareholders' equity	361,153				356,123
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	0		0
Cost of sales	0		0
Gross margin	0		0
Selling, research and development, general and administrative expenses	2,561		976
Acquisition-related expenses	269		362
Restructuring and other expenses	0
Depreciation and amortization	17		11
Total operating costs and expenses	2,847		1,349
Operating income	(2,847)		(1,349)
Equity in net income of subsidiaries	4,971		7,572
Other, net	(8,617)		(8,054)
Total other expense	(3,646)		(482)
Loss before income taxes	(6,493)		(1,831)
Income tax expense (benefit)	0		32
Net income (loss)	(6,493)		(1,863)
Cash flows from operating activities:
Net income (loss)	(6,493)		(1,863)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation, amortization and impairment	16		11
Share-based compensation	866		563
Change in contingent consideration for acquisitions			0
Amortization of note payable issuance costs and discount	736		649
Provision for doubtful accounts receivable and allowances, net of recoveries	0		0
Deferred income taxes	0		0
Unrealized loss on equity security	441
Net change in assets and liabilities (net of effects of acquisitions)	6,552		(4,141)
Net cash provided by operating activities	2,118		(4,781)
Cash flows from investing activities:
Cash paid for acquisitions, net of cash acquired			0
Purchases of property, equipment, and leasehold improvements	0		(62)
Intercompany advances	0		2,470
Net cash used in investing activities	0		2,408
Cash flows from financing activities:
Intercompany advances	500		0
Proceeds from exercise of stock options and employee stock purchase plan	64		745
Principal payments on notes payable	0		0
Principal payments on capital leases	0		0
Net cash provided by financing activities	564		745
Effect of exchange rates on cash and cash equivalents	0		0
Net increase in cash and cash equivalents	2,682		(1,628)
Cash and cash equivalents (net of restricted cash), beginning of period (1)	212		4,907
Cash and cash equivalents (net of restricted cash), end of period (2)	2,894		3,279
Guarantors [Member]
Current assets:
Cash and cash equivalents (including restricted cash)	38,040				32,012
Accounts receivable, net	64,626				61,871
Intercompany receivables	40,585				48,418
Other current assets	31,386				29,337
Total current assets	174,637				171,638
Net property and equipment	3,958				4,187
Purchased and developed software, net	17,359				18,508
Other intangible assets, net	32,623				35,025
Goodwill	212,908				212,908
Investment in and advances to subsidiaries	2,475				(868)
Other assets	3,544				5,745
Total assets	447,504				447,143
Current liabilities:
Accounts payable	23,389				21,839
Deferred revenue	52,990				50,716
Intercompany payables	10,738				13,369
Other accrued liabilities	15,982				18,168
Total current liabilities	103,099				104,092
Notes payable	0				0
Other long-term liabilities	4,735				5,518
Total liabilities	107,834				109,610
Total shareholders' equity	339,670				337,533
Total liabilities and shareholders' equity	447,504				447,143
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	59,022		56,698
Cost of sales	27,568		23,826
Gross margin	31,454		32,872
Selling, research and development, general and administrative expenses	24,934		23,056
Acquisition-related expenses	0		0
Restructuring and other expenses	1,228
Depreciation and amortization	2,577		2,740
Total operating costs and expenses	28,739		25,796
Operating income	2,715		7,076
Equity in net income of subsidiaries	(525)		(472)
Other, net	(30)		59
Total other expense	(555)		(413)
Loss before income taxes	2,160		6,663
Income tax expense (benefit)	2,355		(621)
Net income (loss)	(195)		7,284
Cash flows from operating activities:
Net income (loss)	(195)		7,284
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation, amortization and impairment	4,368		4,587
Share-based compensation	736		605
Change in contingent consideration for acquisitions			(297)
Amortization of note payable issuance costs and discount	0		0
Provision for doubtful accounts receivable and allowances, net of recoveries	150		493
Deferred income taxes	2,111		(307)
Unrealized loss on equity security	0
Net change in assets and liabilities (net of effects of acquisitions)	(4,119)		(5,865)
Net cash provided by operating activities	3,051		6,500
Cash flows from investing activities:
Cash paid for acquisitions, net of cash acquired			(500)
Purchases of property, equipment, and leasehold improvements	(373)		(1,487)
Intercompany advances	(500)		(198)
Net cash used in investing activities	(873)		(2,185)
Cash flows from financing activities:
Intercompany advances	0		0
Proceeds from exercise of stock options and employee stock purchase plan	332		0
Principal payments on notes payable	0		0
Principal payments on capital leases	(103)		(41)
Net cash provided by financing activities	229		(41)
Effect of exchange rates on cash and cash equivalents	0		0
Net increase in cash and cash equivalents	2,407		4,274
Cash and cash equivalents (net of restricted cash), beginning of period (1)	31,849		27,840
Cash and cash equivalents (net of restricted cash), end of period (2)	34,256		32,114
Non-Guarantors [Member]
Current assets:
Cash and cash equivalents (including restricted cash)	5,478				3,001
Accounts receivable, net	7,989				10,194
Intercompany receivables	799				799
Other current assets	3,727				3,702
Total current assets	17,993				17,696
Net property and equipment	624				648
Purchased and developed software, net	465				499
Other intangible assets, net	566				603
Goodwill	1,361				1,404
Investment in and advances to subsidiaries	0				0
Other assets	6,885				7,593
Total assets	27,894				28,443
Current liabilities:
Accounts payable	1,126				1,090
Deferred revenue	1,861				1,639
Intercompany payables	9,682				17,037
Other accrued liabilities	1,237				1,133
Total current liabilities	13,906				20,899
Notes payable	0				0
Other long-term liabilities	601				635
Total liabilities	14,507				21,534
Total shareholders' equity	13,387				6,909
Total liabilities and shareholders' equity	27,894				28,443
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	4,612		4,280
Cost of sales	623		1,157
Gross margin	3,989		3,123
Selling, research and development, general and administrative expenses	(1,485)		3,121
Acquisition-related expenses	0		0
Restructuring and other expenses	1
Depreciation and amortization	59		56
Total operating costs and expenses	(1,425)		3,177
Operating income	5,414		(54)
Equity in net income of subsidiaries	0		0
Other, net	(113)		64
Total other expense	(113)		64
Loss before income taxes	5,301		10
Income tax expense (benefit)	660		194
Net income (loss)	4,641		(184)
Cash flows from operating activities:
Net income (loss)	4,641		(184)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation, amortization and impairment	79		88
Share-based compensation	41		31
Change in contingent consideration for acquisitions			0
Amortization of note payable issuance costs and discount	0		0
Provision for doubtful accounts receivable and allowances, net of recoveries	(65)		31
Deferred income taxes	661		212
Unrealized loss on equity security	0
Net change in assets and liabilities (net of effects of acquisitions)	2,607		274
Net cash provided by operating activities	7,964		452
Cash flows from investing activities:
Cash paid for acquisitions, net of cash acquired			0
Purchases of property, equipment, and leasehold improvements	(20)		(194)
Intercompany advances	(500)		(2,470)
Net cash used in investing activities	(520)		(2,664)
Cash flows from financing activities:
Intercompany advances	500		198
Proceeds from exercise of stock options and employee stock purchase plan	0		0
Principal payments on notes payable	(5)		(27)
Principal payments on capital leases	0		0
Net cash provided by financing activities	495		171
Effect of exchange rates on cash and cash equivalents	81		(12)
Net increase in cash and cash equivalents	8,020		(2,053)
Cash and cash equivalents (net of restricted cash), beginning of period (1)	3,001		5,818
Cash and cash equivalents (net of restricted cash), end of period (2)	11,021		3,765
Eliminations [Member]
Current assets:
Cash and cash equivalents (including restricted cash)	0				0
Accounts receivable, net	0				0
Intercompany receivables	(42,535)				(50,359)
Other current assets	0				0
Total current assets	(42,535)				(50,359)
Net property and equipment	0				0
Purchased and developed software, net	0				0
Other intangible assets, net	0				0
Goodwill	0				0
Investment in and advances to subsidiaries	(353,117)				(344,496)
Other assets	0				0
Total assets	(395,652)				(394,855)
Current liabilities:
Accounts payable	0				0
Deferred revenue	0				0
Intercompany payables	(42,595)				(50,414)
Other accrued liabilities	0				0
Total current liabilities	(42,595)				(50,414)
Notes payable	0				0
Other long-term liabilities	0				0
Total liabilities	(42,595)				(50,414)
Total shareholders' equity	(353,057)				(344,441)
Total liabilities and shareholders' equity	(395,652)				(394,855)
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	0		0
Cost of sales	0		0
Gross margin	0		0
Selling, research and development, general and administrative expenses	0		0
Acquisition-related expenses	0		0
Restructuring and other expenses	0
Depreciation and amortization	0		0
Total operating costs and expenses	0		0
Operating income	0		0
Equity in net income of subsidiaries	(4,446)		(7,100)
Other, net	0		0
Total other expense	(4,446)		(7,100)
Loss before income taxes	(4,446)		(7,100)
Income tax expense (benefit)	0		0
Net income (loss)	(4,446)		(7,100)
Cash flows from operating activities:
Net income (loss)	(4,446)		(7,100)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation, amortization and impairment	0		0
Share-based compensation	0		0
Change in contingent consideration for acquisitions			0
Amortization of note payable issuance costs and discount	0		0
Provision for doubtful accounts receivable and allowances, net of recoveries	0		0
Deferred income taxes	0		0
Unrealized loss on equity security	0
Net change in assets and liabilities (net of effects of acquisitions)	0		7,100
Net cash provided by operating activities	(4,446)		0
Cash flows from investing activities:
Cash paid for acquisitions, net of cash acquired			0
Purchases of property, equipment, and leasehold improvements	0		0
Intercompany advances	1,000		198
Net cash used in investing activities	1,000		198
Cash flows from financing activities:
Intercompany advances	(1,000)		(198)
Proceeds from exercise of stock options and employee stock purchase plan	0		0
Principal payments on notes payable	0		0
Principal payments on capital leases	0		0
Net cash provided by financing activities	(1,000)		(198)
Effect of exchange rates on cash and cash equivalents	0		0
Net increase in cash and cash equivalents	(4,446)		0
Cash and cash equivalents (net of restricted cash), beginning of period (1)	0		0
Cash and cash equivalents (net of restricted cash), end of period (2)	$ (4,446)		$ 0

[1] Net of restricted cash of $813 and $707 at December 31, 2012 and 2011, respectively

[2] Net of restricted cash of $813 at December 31, 2012

[3] Net of restricted cash of $707 at December 31, 2011

[4] Net of restricted cash of $813 and $707 at March 31, 2013 and 2012, respectively.

[5] Net of restricted cash of $813 at March 31, 2013

[6] Net of restricted cash of $707 at March 31, 2012