Notes Payable and Subordinated Borrowings Schedule of Debt (Details) $ in Thousands	Jun. 30, 2016 USD ($)
Series A Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage (as a percent)	5.16%
Long-term Debt	$ 37,555
Series B Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage (as a percent)	5.44%
Long-term Debt	$ 66,203
Series C Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage (as a percent)	5.64%
Long-term Debt	$ 47,423
Series D Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage (as a percent)	5.72%
Long-term Debt	$ 16,795
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 167,976