Debt Obligations - Japan and Hong Kong Credit Facility (Details) - Revolving Credit Facilities	1 Months Ended	12 Months Ended
	Nov. 30, 2017 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2018 HKD ($)	Nov. 30, 2017 JPY (¥)	Nov. 30, 2017 HKD ($)	Apr. 01, 2017 USD ($)	Apr. 01, 2017 HKD ($)
Japan Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 9,400,000			¥ 1,000,000,000.0
Line of credit, current obligations		$ 0
Japan Credit Facility | Bank Rate Two Days Prior | Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	0.30%
HK Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 12,700,000				$ 100,000,000.0
Line of credit, current obligations		0				$ 5,800,000	$ 45,000,000
Minimum commitment, amount					5,000,000
Line of credit facility, available for future borrowings		$ 11,200,000	$ 88,200,000
HK Credit Facility | Business Card Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 100,000				$ 400,000.0
HK Credit Facility | HIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate		1.50%
HK Credit Facility, Bank Guarantees | Revolving Credit Facility
Line of Credit Facility [Line Items]
Bank guarantees supported by facility		$ 1,500,000	$ 11,800,000