Investment Management Transfer Agent and Other Fees - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended		1 Months Ended		3 Months Ended		9 Months Ended				9 Months Ended
	Dec. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013 Investor Class Shares	Dec. 31, 2013 Institutional Class Shares	Mar. 31, 2014 Offshore Funds	Mar. 31, 2013 Offshore Funds	Mar. 31, 2014 Offshore Funds	Mar. 31, 2013 Offshore Funds	Mar. 31, 2014 Offshore Funds Investment Advisory Services company	Nov. 30, 2013 Offshore Funds Investment Advisory Services fund	Mar. 31, 2014 Government Fund	Mar. 31, 2014 U.S. Treasury Securities Cash Fund
Investment Management And Other Fees [Line Items]
Base advisory fee adjustment, description	Is adjusted upwards or downwards by 0.25 percent when there is a performance difference of 5 percent or more between a fund’s performance and that of its designated benchmark index over the prior rolling 12 months.
Base percentage adjustment when fund performance is not within limits to benchmark index		0.25%		0.25%
Percent minimum performance to designated benchmark over prior rolling 12 months		5.00%		5.00%
Increase (decrease) in base advisory fees realized		$ (213,643)	$ 108,969	$ (632,324)	$ (56,095)
Aggregate fees waived and expenses borne		354,118	798,138	2,102,329	2,502,737
Fees waived and or expenses reimbursed U.S. Treasury Securities Cash Fund to maintain minimum yield		0	298,128	583,577	885,273
Minimum yield waivers recoverable through 12/31/14														736,531
Minimum yield waivers recoverable through 12/31/15														509,874
Minimum yield waivers recoverable through 12/31/16														498,342
Minimum yield waivers subject to future recovery															0
Previous administrative fee rate						0.08%	0.06%
Current annual administrative fee rate						0.10%	0.08%
Administrative services fees on average daily net assets	10,000
Number of offshore clients company provides advisory services for												3
Number of funds liquidated													1
Recorded advisory and performance fees								$ 42,334	$ 83,960	$ 147,402	$ 253,534