Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Acquisitions and Dispositions Identified Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Accumulated Amortization through December 31, 2019	$ 37,357	$ 33,487	$ 33,807
1st Global
Business Acquisition [Line Items]
Estimated Fair Value	83,980
Accumulated Amortization through December 31, 2019	4,936
Advisor relationships \| 1st Global
Business Acquisition [Line Items]
Estimated Fair Value	78,400
Accumulated Amortization through December 31, 2019	$ 3,568
Weighted Average Estimated Remaining Useful Life (in months)	196 months
Developed technology \| 1st Global
Business Acquisition [Line Items]
Estimated Fair Value	$ 2,980
Accumulated Amortization through December 31, 2019	$ 916
Weighted Average Estimated Remaining Useful Life (in months)	29 months
Trade name \| 1st Global
Business Acquisition [Line Items]
Estimated Fair Value	$ 1,000
Accumulated Amortization through December 31, 2019	$ 218
Weighted Average Estimated Remaining Useful Life (in months)	29 months
Training materials \| 1st Global
Business Acquisition [Line Items]
Estimated Fair Value	$ 900
Accumulated Amortization through December 31, 2019	$ 196
Weighted Average Estimated Remaining Useful Life (in months)	29 months
Sponsor relationships \| 1st Global
Business Acquisition [Line Items]
Estimated Fair Value	$ 700
Accumulated Amortization through December 31, 2019	$ 38
Weighted Average Estimated Remaining Useful Life (in months)	137 months