Debt - Additional Information (Detail) (USD $)	6 Months Ended		6 Months Ended				6 Months Ended
	Mar. 31, 2013 Installment Vehicle	Jun. 30, 2011	Mar. 31, 2013 Term Note	Mar. 31, 2013 Second Term Note	Jul. 05, 2012 Second Term Note	May 11, 2012 Second Term Note	Mar. 31, 2013 Third Term Note Dawson Seismic Services ULC	Mar. 31, 2013 Option Two	Mar. 31, 2013 Option One
Debt Instrument [Line Items]
Borrowing, repaying and reborrowing capacity	$ 20,000,000					$ 15,000,000
Line of credit facility, interest rate description	Interest on the facility accrues at an annual rate equal to either the 30-day London Interbank Offered Rate ("LIBOR"), plus two and one-quarter percent, or the Prime Rate, minus three-quarters percent, as the Company directs monthly, subject to an interest rate floor of 4%
Line of credit facility agreement effective date	Jun. 02, 2011
Line of credit facility agreement expiry date	Jun. 02, 2013
Term Note, interest rate description								30-day London Interbank Offered Rate ("LIBOR"), plus two and one-quarter percent	Prime Rate, minus three-quarters percent
Term Note interest rate over which, interest is to be paid separately			4.00%	3.75%
Covenant compliance of line of credit facility	The Company was in compliance with all covenants including specified ratios as of March 31, 2013 and April 30, 2013
Line of credit facility utilized	0
Funds obtained under term notes		16,427,000			9,346,000		983,000
Line of credit facility amendment date	Jun. 30, 2011
Term Note repayable over a period			36 months				36 months
Monthly term note repayment amount	$ 485,444						$ 28,980
Maturity of term loans			Jun. 30, 2014	May 02, 2015			Feb. 05, 2016
Term Note, frequency of interest payment	Monthly
Term note interest rate							3.84%
No of installments in which capital leases are payable, minimum	36
No of installments in which capital leases are payable, maximum	60
Capital lease obligations maturity period	December 2014 and November 2017.
No of vehicles leased under capital leases	83