Discontinued Operations - Additional Information (Detail)	3 Months Ended	12 Months Ended			1 Months Ended	3 Months Ended		1 Months Ended	12 Months Ended
	Aug. 03, 2011	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Mar. 18, 2011 Navis, LLC [Member] USD ($)	Mar. 31, 2012 Navis, LLC [Member] USD ($)	Sep. 30, 2012 Navis, LLC [Member] USD ($)	Aug. 03, 2011 Proveo AG [Member] USD ($)	Dec. 31, 2012 Proveo AG [Member] USD ($)	Dec. 31, 2012 Proveo AG [Member] EUR (€)	Jun. 30, 2012 Proveo AG [Member] EUR (€)	Aug. 03, 2011 Proveo AG [Member] EUR (€)
Proceeds from the sale of business		$ 27,580,000	$ 161,206,000	$ 0	$ 188,588,000
Short-term receivable from buyer		0	27,580,000				13,790,000
Receivable from Previously escrowed funds						13,790,000
Gain (loss) recorded upon divestiture		930,000	68,745,000	0				1,248,000	930,000
Loan agreed to provide to the buyer											526,058	1,000,000
Loan, duration (date)	Aug. 03, 2012	Dec. 31, 2012
Loan, interest rate											6.50%	6.50%
Tax benefits realized		0	11,773,000	0				13,308,000
Outstanding Loan										€ 376,058