Related Party Transactions (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Oct. 31, 2013	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Fair value		$ 163,793		$ 163,793		$ 181,138
SP Corporate Services LLC
Provision of services		2,400	$ 2,200	4,600	$ 4,400
Accounts payable		300		300
Mutual Securities, Inc.
Paid commissions		18	99	29	222
iGo
Fixed annual fee	$ 400
WebBank | Interest Income
Interest income		12	$ 21	28	$ 42
WebBank | Short-term deposits
Short-term deposits		$ 6,300		$ 6,300
Steel Partners
Shares authorized		1,000,000		1,000,000
Common units (in shares)		204,712		204,712
Fair value		$ 3,600		$ 3,600