Fair Values of Assets and Liabilities Transfers Between Level 1 and Level 2 (Details) - Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] - USD ($) $ in Thousands	Sep. 30, 2016	Mar. 31, 2016
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$ 0	$ 0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	0	0
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount	0	0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount	0	0
Held-to-maturity Securities, Fair Value	$ 0	$ 0