Fair Value Measurements (Narrative) (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]
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 Assets Level 1 To Level 3 Transfers Amount	0	0
Fair Value Assets Level 3 To Level 1 Transfers Amount	0	0
Fair Value Assets Level 2 To Level 3 Transfers Amount	0	0
Fair Value Assets Level 3 To Level 2 Transfers Amount	$ 0	$ 0