Acquisitions Fillmore Advisors, LLC Acquisition (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 01, 2019	Apr. 01, 2019
Coininvest and EPMT Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents			$ 2.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets			1.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets			15.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable			0.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			0.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net			15.2
Business Combination, Consideration Transferred	$ 22.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles			2.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill			$ 4.6
Fillmore Advisors, LLC [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		$ 0.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		0.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		1.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		0.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		0.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		0.6
Goodwill, Acquired During Period	1.9
Business Combination, Consideration Transferred	3.2
Payments to Acquire Businesses, Gross	$ 1.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		0.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		0.7
Business Combination, Contingent Consideration, Liability		1.8
Cash [Member] | Fillmore Advisors, LLC [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability		$ 1.8