Revenues (Tables)

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

The following table summarizes revenue by source:

	Years Ended December 31,
($ in thousands)	2018		2017 (1)		2016 (1)
Investment management fees
Open-end funds	$	231,175	$	175,260	$	129,542
Closed-end funds	41,455		44,687		43,342
Retail separate accounts	73,532		54,252		40,155
Institutional accounts	77,711		46,600		18,707
Structured products	9,622		6,302		2,211
Other products	3,526		3,974		1,273
Total investment management fees	437,021		331,075		235,230
Distribution and service fees	50,715		44,322		48,250
Administration and shareholder service fees	63,614		48,996		38,261
Other income and fees	885		1,214		813
Total revenues	$	552,235	$	425,607	$	322,554

(1)    Prior period amounts have not been adjusted and are reported in accordance with historical accounting under ASC 605, Revenue Recognition

Schedule of New Accounting Pronouncements and Changes in Accounting Principles

The impact of adoption of ASC 606 on the Company's consolidated statement of operations was as follows:

	Year Ended December 31, 2018
($ in thousands)	As Reported		Balance Under Prior ASC 605		Effect of Change Higher/(Lower)
Revenues
Distribution and service fees	$	50,715	$	44,739	$	5,976
Operating Expenses
Distribution and other asset-based expenses	$	92,441	$	86,465	$	5,976