Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 28, 2014	Sep. 29, 2013
Current assets:
Cash and cash equivalents	$ 122,379	$ 129,305
Accounts receivable - net	701,892	660,847
Prepaid expenses and other current assets	52,256	61,446
Income taxes receivable	22,076	20,044
Total current assets	898,603	871,642
Property and equipment - net	73,864	88,026
Investments in and advances to unconsolidated joint ventures	2,140	2,198
Goodwill	714,190	722,792
Intangible assets - net	63,095	86,929
Other long-term assets	24,512	27,505
Total assets	1,776,404	1,799,092
Current liabilities:
Accounts payable	175,952	142,813
Accrued compensation	110,186	114,810
Billings in excess of costs on uncompleted contracts	103,343	79,507
Deferred income taxes	20,387	18,170
Current portion of long-term debt	10,989	4,311
Estimated contingent earn-out liabilities	3,568	23,281
Other current liabilities	79,436	100,241
Total current liabilities	503,861	483,133
Deferred income taxes	28,786	30,525
Long-term debt	192,842	203,438
Long-term estimated contingent earn-out liabilities	3,462	58,508
Other long-term liabilities	34,397	24,685
Commitments and contingencies
Equity:
Preferred stock - Authorized, 2,000 shares of $0.01 par value; no shares issued and outstanding at September 28, 2014, and September 29, 2013
Common stock - Authorized, 150,000 shares of $0.01 par value; issued and outstanding, 62,591 and 64,134 shares at September 28, 2014, and September 29, 2013, respectively	626	641
Additional paid-in capital	402,516	443,099
Accumulated other comprehensive income (loss)	(42,538)	1,858
Retained earnings	651,475	552,165
Tetra Tech stockholders' equity	1,012,079	997,763
Noncontrolling interests	977	1,040
Total equity	1,013,056	998,803
Total liabilities and equity	$ 1,776,404	$ 1,799,092