Stock-Based Compensation (Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Feb. 28, 2018 metric	Nov. 30, 2019 USD ($) period plan $ / shares shares	Nov. 30, 2018 $ / shares shares	Nov. 30, 2017 USD ($) $ / shares Executives shares	Nov. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shareholder approved stock plans | plan		1
Number of plans for which shareholder approval not required | plan		2
Unrecognized stock-based compensation expense, net of expected forfeitures | $		$ 28.7
Costs are expected to be recognized, weighted average period		2 years
Number of executives whose employment was terminated | Executives				3
Additional stock-based compensation expenses related to separation and acceleration vesting | $				$ 1.5
2008 Stock Option and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under stock plans (in shares)		54,510,000
Shares available for grant under stock plans (in shares)		4,145,680
2002 Nonqualified Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under stock plans (in shares)		9,750,000
Shares available for grant under stock plans (in shares)		400,046
2004 Inducement Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under stock plans (in shares)		1,500,000
Shares available for grant under stock plans (in shares)		453,796
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional stock-based compensation expenses related to separation and acceleration vesting | $				0.8
Product development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional stock-based compensation expenses related to separation and acceleration vesting | $				$ 0.7
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Number of common stock shares each restricted stock unit represents (in shares)		1
Stock-based compensation service period		3 years		3 years	3 years
Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation service period	3 years
Number of performance metrics | metric	2
Percentage of shares based on market conditions	50.00%
Market condition period	3 years
Percentage of shares based on cumulative performance condition	50.00%
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under stock plans (in shares)		9,450,000
ESPP offering period		27 months
ESPP number of purchase periods | period		9
ESPP purchase period		3 months
ESPP purchase price (as a percent)		85.00%
Employee stock purchase plan, issued shares (in shares)		189,000	225,000	220,000
Weighted average purchase price of shares (in dollars per share) | $ / shares		$ 29.23	$ 24.27	$ 22.27
Shares available and reserved for issuance (in shares)		401,000
Additional holding period		3 months
Weighted average estimated fair value of options granted, per share (in dollars per share) | $ / shares		$ 11.07	10.24	8.32
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Weighted average estimated fair value of options granted, per share (in dollars per share) | $ / shares		$ 7.38	$ 10.30	$ 5.95