Provision for Income Taxes (Details Textual) (USD $)							12 Months Ended
Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2014 Domestic Tax Authority [Member]	Apr. 30, 2013 Domestic Tax Authority [Member]	Apr. 30, 2014 Foreign Tax Authority [Member]	Apr. 30, 2013 Foreign Tax Authority [Member]	Apr. 30, 2014 State and Local Jurisdiction [Member]
Operating Loss Carryforwards			$ 15,426,000	$ 11,216,000	$ 1,034,000	$ 1,744,000
Deferred Tax Assets, Valuation Allowance	$ 10,968,000	$ 8,948,000
Operating Loss Carry forwards Expiration Year							begin expiring in 2029.

Expiration year of each operating loss carryforward included in operating loss carryforward.

No definition available.

Name:	csbr_OperatingLossCarryForwardsExpirationYear
Namespace Prefix:	csbr_
Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

+ Details

Name:	us-gaap_OperatingLossCarryforwards
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant