v2.4.0.6

Net loss per share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
Common Class A [Member]
Numerator:
Allocation of distributed net loss attributable to common stockholders	$ (3,807)		$ (3,939)
Denominator:
Weighted-average common shares outstanding	5,688		1,910
Basic and diluted net loss per share	$ (0.67)	$ 0.00	$ (2.06)	$ 0.00
Common Class B [Member]
Numerator:
Allocation of distributed net loss attributable to common stockholders	$ (37,664)	$ (19,803)	$ (84,875)	$ (56,128)
Denominator:
Weighted-average common shares outstanding	56,272	29,779	41,143	29,013
Basic and diluted net loss per share	$ (0.67)	$ (0.66)	$ (2.06)	$ (1.93)

X

- Definition

The total amount of dividends declared in the period for each class of stock and the contractual amount of dividends (or interest on participating income bonds) that must be paid for the period (for example, unpaid cumulative dividends). Dividends declared in the current period do not include dividends declared in respect of prior-period unpaid cumulative dividends. Preferred dividends that are cumulative only if earned are deducted only to the extent that they are earned.

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