Segment Information - Table (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenues	$ 44,452	$ 56,237	$ 60,346	$ 50,080	$ 45,370	$ 48,047	$ 51,884	$ 44,569	$ 211,115	$ 189,870	$ 174,076
Pre-tax income (loss)	(3,294)	$ 1,413	$ (674)	$ (5,767)	5,293	$ (62)	$ 5,610	$ 5,738	(8,322)	16,579	(2,469)
Identifiable assets	68,449				64,398				68,449	64,398	60,546
Depreciation and amortization									1,551	1,229	1,213
Interest									97	14	51
Capital expenditures									938	1,672	932
Corporate
Segment Reporting Information [Line Items]
Revenues									0	0	0
Pre-tax income (loss)									(14,393)	4,414	(6,175)
Identifiable assets	12,096				14,201				12,096	14,201	14,386
Depreciation and amortization									539	354	272
Capital expenditures									331	1,459	709
Brokerage and Advisory Services | Operating Segments
Segment Reporting Information [Line Items]
Revenues									203,343	182,431	165,682
Pre-tax income (loss)									5,176	11,516	4,227
Identifiable assets	51,946				47,213				51,946	47,213	43,851
Depreciation and amortization									749	694	760
Interest									97	14	51
Capital expenditures									564	140	127
Tax and Accounting Services | Operating Segments
Segment Reporting Information [Line Items]
Revenues									7,772	7,439	8,394
Pre-tax income (loss)									895	649	(521)
Identifiable assets	$ 4,407				$ 2,984				4,407	2,984	2,309
Depreciation and amortization									263	181	181
Capital expenditures									$ 43	$ 73	$ 96