Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020
Liabilities:
Liquidating distributions payable	$ 54,314	$ 351,876
Fair Value, Measurements, Recurring [Member]
Assets:
Total Assets	130,108	433,190
Liabilities:
Liquidating distributions payable	54,314	351,876
Fair Value, Measurements, Recurring [Member] | Cash equivalents [Member] | Money Market Funds [Member]
Assets:
Total Assets	95	40,413
Fair Value, Measurements, Recurring [Member] | Marketable Securities [Member] | U.S. Treasury Bills [Member]
Assets:
Total Assets	130,013	392,777
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets:
Total Assets	95	40,413
Liabilities:
Liquidating distributions payable	54,314	351,876
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Cash equivalents [Member] | Money Market Funds [Member]
Assets:
Total Assets	95	40,413
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets:
Total Assets	130,013	392,777
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Marketable Securities [Member] | U.S. Treasury Bills [Member]
Assets:
Total Assets	$ 130,013	$ 392,777