Implementation of the New Revenue Recognition Standard - Cumulative effect on Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Oct. 01, 2018	Sep. 30, 2018
Current assets:
Accounts receivable - net	$ 157,532	$ 155,624	$ 392,367
Contract assets	296,920	272,210
Recoverable income taxes	5,910	91	91
Inventories	119,870	61,688	84,199
Assets held for sale	12,620	8,177	8,177
Other current assets		43,705	43,705
Total current assets	709,242	681,103	668,147
Long-term contracts receivables			6,134
Long-term contracts financing receivables			6,134
Property, plant and equipment, net	129,367	117,546	117,546
Deferred income taxes	4,798	5,102	4,713
Goodwill	579,648	333,626	333,626
Purchased intangibles, net	184,104	73,533	73,533
Other assets	14,290
Total assets	1,733,100	1,321,130	1,304,883
Current liabilities:
Short-term borrowings	209,000
Contract liabilities	78,352	70,127
Customer advances			75,941
Accrued compensation and other current liabilities		118,816	118,233
Income taxes payable	2,690	8,586	8,586
Total current liabilities	524,058	320,097	328,339
Shareholders' equity:
Common stock	264,612	45,008	45,008
Retained earnings	801,486	821,668	801,834
Accumulated other comprehensive loss	(110,156)	(110,643)	(110,643)
Treasury stock at cost	(36,078)	(36,078)	(36,078)
Shareholders’ equity related to Cubic	919,864	719,955	700,121
Noncontrolling interest in consolidated VIE	23,325	28,730	24,075
Total shareholders’ equity	943,189	748,685	724,196
Total liabilities and shareholders' equity	1,733,100	1,321,130	1,304,883
Cubic Corporation Excluding VIE
Current assets:
Cash and cash equivalents	42,483	111,834	111,834
Restricted cash	19,064	17,400	17,400
Other current assets	44,471		43,705
Long-term contracts financing receivables	41,758	56,228
Long-term capitalized contract costs			84,924
Other assets	14,290	14,192	14,192
Current liabilities:
Trade accounts payable	129,686	122,403	125,414
Accrued compensation and other current liabilities	93,256		118,233
Long-term debt	189,095	199,793	199,793
Other long term liabilities	41,290	43,486	43,486
OpCo.
Current assets:
Cash and cash equivalents	362	374	374
Restricted cash	9,967	10,000	10,000
Other current assets	43
Long-term contracts financing receivables	68,779	38,990
Long-term capitalized contract costs			1,258
Other assets	1,114	810	810
Current liabilities:
Trade accounts payable	156	165	165
Accrued compensation and other current liabilities	204
Long-term debt	25,602	9,056	9,056
Other long term liabilities	9,866	$ 13	13
ASU 2014-09 | ASC 606
Current assets:
Accounts receivable - net	(248,648)		(236,743)
Contract assets	296,920		272,210
Recoverable income taxes	210
Inventories	(33,165)		(22,511)
Total current assets	15,317		12,956
Long-term contracts receivables	(3,474)		(6,134)
Deferred income taxes	235		389
Total assets	11,451		16,247
Current liabilities:
Contract liabilities	78,352		70,127
Customer advances	(100,520)		(75,941)
Accrued compensation and other current liabilities			583
Income taxes payable	456
Total current liabilities	(24,066)		(8,242)
Shareholders' equity:
Retained earnings	26,384		19,834
Shareholders’ equity related to Cubic	26,384		19,834
Noncontrolling interest in consolidated VIE	9,133		4,655
Total shareholders’ equity	35,517		24,489
Total liabilities and shareholders' equity	11,451		16,247
ASU 2014-09 | Cubic Corporation Excluding VIE | ASC 606
Current assets:
Long-term contracts financing receivables	41,758		56,228
Long-term capitalized contract costs	(109,318)		(84,924)
Current liabilities:
Trade accounts payable	(2,354)		(3,011)
ASU 2014-09 | OpCo. | ASC 606
Current assets:
Long-term contracts financing receivables	68,779		38,990
Long-term capitalized contract costs	$ (1,846)		$ (1,258)