Goodwill and Other Intangibles (Detail 2) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Other Intangible Assets
Gross Carrying Amount	$ 62,764		$ 62,764		$ 62,764
Accumulated Amortization	32,779		32,779		31,169
Other intangible assets not subject to amortization	8,900		8,900
Amortization expense of other intangible assets	800	$ 1,200	1,600	$ 2,500
Impairment of other intangible assets			0
Trade name
Other Intangible Assets
Gross Carrying Amount	8,545		8,545		8,545
Trading rights
Other Intangible Assets
Gross Carrying Amount	339		339		339
Other
Other Intangible Assets
Gross Carrying Amount	50		50		50
POSIT trade name
Other Intangible Assets
Other intangible assets not subject to amortization	8,400		8,400
Customer related intangibles
Other Intangible Assets
Gross Carrying Amount	30,272		30,272		30,272
Accumulated Amortization	12,398		$ 12,398		11,210
Useful Lives			13 years 3 months 18 days
Proprietary software
Other Intangible Assets
Gross Carrying Amount	23,558		$ 23,558		23,558
Accumulated Amortization	$ 20,381		$ 20,381		$ 19,959
Useful Lives			6 years 3 months 18 days