Fair Value Measurements (Detail) (USD $)						0 Months Ended
	Jun. 30, 2013	Jun. 11, 2013	Dec. 31, 2012	Jun. 30, 2013 Three Point Seven Five Percent Unsecured Convertible Subordinated Debentures Due In 2026 [Member]	Nov. 30, 2012 Three Point Seven Five Percent Unsecured Convertible Subordinated Debentures Due In 2026 [Member]	Jun. 11, 2013 "School Specialties" [Member]	Jan. 28, 2013 "School Specialties" [Member]	Dec. 31, 2012 Marketable Securities [Member]	Jun. 30, 2013 Senior Notes [Member] Convertible Senior Subordinted Notes Due 2023 [Member]	Dec. 31, 2012 Senior Notes [Member] Convertible Senior Subordinted Notes Due 2023 [Member]
Investment Owned, Balance, Principal Amount								$ 11,900,000
3/4% convertible senior subordinated notes due 2023 (as a percent)									0.75%	0.75%
Investment Owned, at Cost				9,800,000	6,000,000
Debtor-in-Possession Financing, Amount Arranged							21,300,000
Shares Received in Exchange for Convertible Debentures (in shares)						26,457
Debtor in Possession, Cash Received in Exchange for Investment in Loan						17,500,000
Shares Received in Exchange for Investment in Loan (in shares)		49,136
Debtor in Possession, Fair Value of Shares Received (in dollars per share)		$ 109
Debtor in Possession, Gain (Loss) on Disposal of Investment in Loan						3,200,000
Debtor in Possession, Gain (Loss) on Disposal of Loan						1,600,000
Convertible Notes Payable, Current	$ 346,000		$ 346,000						$ 300,000	$ 346,000