Summary Of Significant Accounting Policies (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended			9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Minimum [Member]	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2013 Stock Options And SARs [Member]	Sep. 30, 2013 Stock Options [Member]	Sep. 30, 2013 Stock Appreciation Rights (SARs) [Member] Minimum [Member]	Sep. 30, 2013 Stock Appreciation Rights (SARs) [Member] Maximum [Member]	Sep. 30, 2013 Restricted Stock Awards And Units [Member] Minimum [Member]	Sep. 30, 2013 Restricted Stock Awards And Units [Member] Maximum [Member]	Sep. 30, 2013 Restricted Stock Granted To Contractors [Member]	Dec. 27, 2012 Carrizo United Kingdom [Member]
Summary Of Significant Accounting Policies [Line Items]
shares excluded from the calculation of dilutive shares		402,750
Internal costs capitalized, Oil and Gas Producing Activities	$ 3,800,000	$ 2,500,000	$ 10,100,000	$ 9,500,000
Percentage of non-operating working interest and overriding royalty interests															15.00%
Allowance for doubtful accounts	600,000		600,000		1,400,000
Average DD&A Per Boe (in USD per BOE)	20.01	19.76	19.59	17.21
Oil and Gas, Exploratory Period			5 years
Capitalized interest	7,485,000	5,917,000	21,791,000	17,951,000
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	$ 0	$ 0	$ 37,294,000	$ 0
Reserves discount factor			10.00%
Estimated useful life, years						5 years	10 years
Vesting period, in years								3 years				1 year	3 years	3 years
Expiration period after date of grant, in years									10 years	4 years	7 years