CONSOLIDATED SCHEDULE OF INVESTMENTS (Unaudited) (USD $)	9 Months Ended		12 Months Ended
	Dec. 31, 2012		Mar. 31, 2012
Schedule of Investments [Line Items]
Cost	$ 87,628,000		$ 88,993,000
Value	551,278,000		558,546,000
ALAMO GROUP INC. [Member]
Schedule of Investments [Line Items]
Location	Seguin, Texas	[1],[2],[3]	Seguin, Texas	[1],[2],[3],[4]
Description of company	Tractor-mounted mowing and mobile excavation equipment for governmental, industrial and agricultural markets; street-sweeping equipment for municipalities.	[1],[2],[3]	Tractor-mounted mowing and mobile excavation equipment for governmental, industrial and agricultural markets; street-sweeping equipment for municipalities.	[1],[2],[3],[4]
Equity (in hundredths)	22.00%	[1],[2],[3],[5]	22.00%	[1],[2],[3],[4],[5]
Investment	2,832,300 shares common stock (acquired 4-1-73 thru 5-09-11)	[1],[2],[3],[6],[7]	2,832,300 shares common stock (acquired 4-1-73 thru 5-09-11)	[1],[2],[3],[4],[6],[7]
Cost	2,190,937	[1],[2],[3]	2,190,937	[1],[2],[3],[4]
Value	92,397,312	[1],[2],[3],[8]	85,138,938	[1],[2],[3],[4],[8]
ATLANTIC CAPITAL BANCSHARES, INC. [Member]
Schedule of Investments [Line Items]
Location	Atlanta, Georgia	[2],[3]	Atlanta, Georgia	[2],[3]
Description of company	Holding company of Atlantic Capital Bank, a full service commercial bank.	[2],[3]	Holding company of Atlantic Capital Bank, a full service commercial bank.	[2],[3]
Equity (in hundredths)	1.90%	[2],[3],[5]	1.90%	[2],[3],[5]
Investment	300,000 shares common stock (acquired 4-10-07)	[2],[3],[6]	300,000 shares common stock (acquired 4-10-07)	[2],[3],[6]
Cost	3,000,000	[2],[3]	3,000,000	[2],[3]
Value	2,534,000	[2],[3],[8]	2,299,000	[2],[3],[8]
BALCO, INC. [Member]
Schedule of Investments [Line Items]
Location	Wichita, Kansas	[2],[3]	Wichita, Kansas	[2],[3],[9]
Description of company	Specialty architectural products used in the construction and remodeling of commercial and institutional buildings.	[2],[3]	Specialty architectural products used in the construction and remodeling of commercial and institutional buildings.	[2],[3],[9]
Equity (in hundredths)	95.70%	[2],[3],[5]	95.70%	[2],[3],[5],[9]
Investment	445,000 shares common stock and 60,920 shares Class B non-voting common stock (acquired 10-25-83 and 5-30-02)	[2],[3],[6]	445,000 shares common stock and 60,920 shares Class B non-voting common stock (acquired 10-25-83 and 5-30-02)	[2],[3],[6],[9]
Cost	624,920	[2],[3]	624,920	[2],[3],[9]
Value	4,600,000	[2],[3],[8]	4,100,000	[2],[3],[8],[9]
BOXX TECHNOLOGIES, INC. [Member]
Schedule of Investments [Line Items]
Location	Austin, Texas	[2],[3],[4]	Austin, Texas	[2],[3],[4]
Description of company	Workstations for computer graphic imaging and design.	[2],[3],[4]	Workstations for computer graphic imaging and design.	[2],[3],[4]
Equity (in hundredths)	14.90%	[2],[3],[4],[5]	14.90%	[2],[3],[4],[5]
Investment	3,125,354 shares Series B Convertible Preferred Stock, convertible into 3,125,354 shares of common stock at $0.50 per share (acquired 8-20-99 thru 8-8-01)	[2],[3],[4],[6]	3,125,354 shares Series B Convertible Preferred Stock, convertible into 3,125,354 shares of common stock at $0.50 per share (acquired 8-20-99 thru 8-8-01)	[2],[3],[4],[6]
Cost	1,500,000	[2],[3],[4]	1,500,000	[2],[3],[4]
Value	1,220,000	[2],[3],[4],[8]	600,000	[2],[3],[4],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member]
Schedule of Investments [Line Items]
Location	Houston, Texas	[2],[3]	Houston, Texas	[2],[3]
Description of company	Cleans above ground oil storage tanks with a patented, automated system.	[2],[3]	Cleans above ground oil storage tanks with a patented, automated system.	[2],[3]
Equity (in hundredths)	73.40%	[2],[3],[5]	73.40%	[2],[3],[5]
Cost	14,322,885	[2],[3]	13,563,842	[2],[3]
Value	2,654,001	[2],[3],[8]	6,002,348	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	12% subordinated secured promissory note, due 5-9-2016 (acquired 5-19-10 thru 10-20-10)	[2],[3],[6]	12% subordinated secured promissory note, due 5-9-2016 (acquired 5-19-10 thru 10-20-10)	[2],[3],[6]
Cost	779,278	[2],[3]	779,278	[2],[3]
Value	183,000	[2],[3],[8]	444,189	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	12% subordinated secured promissory note, due 5-9-2017 (acquired 5-9-11 thru 10-26-11)	[2],[3],[6]	12% subordinated secured promissory note, due 5-9-2017 (acquired 5-9-11 thru 10-26-11)	[2],[3],[6]
Cost	2,285,700	[2],[3]	2,285,700	[2],[3]
Value	537,000	[2],[3],[8]	1,302,849	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 3 [Member]
Schedule of Investments [Line Items]
Investment	12% subordinated secured promissory note, due 3-31-2017 (acquired 9-9-11 and 10-26-11)	[2],[3],[6]	12% subordinated secured promissory note, due 8-31-2016 (acquired 9-9-11 and 10-26-11)	[2],[3],[6]
Cost	1,523,800	[2],[3]	1,264,754	[2],[3]
Value	358,000	[2],[3],[8]	720,910	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 4 [Member]
Schedule of Investments [Line Items]
Investment	10% subordinated secured promissory note, due 5-9-2017 (acquired 7-14-08 thru 4-28-10)	[2],[3],[6]	10% subordinated secured promissory note, due 5-9-2017 (acquired 7-14-08 thru 4-28-10)	[2],[3],[6]
Cost	6,200,700	[2],[3]	6,200,700	[2],[3]
Value	1,458,000	[2],[3],[8]	3,534,399	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 5 [Member]
Schedule of Investments [Line Items]
Investment	12% subordinated secured promissory note, due 10-31-17 (acquired 10-19-12)	[2],[3],[6]	3,033,410 shares Series A Convertible Preferred Stock, convertible into 3,033,410 shares common stock at $1.00 per share (acquired 7-14-08 thru 11-18-10)	[2],[3],[6]
Cost	499,997	[2],[3]	3,033,410	[2],[3]
Value	118,000	[2],[3],[8]	1	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 6 [Member]
Schedule of Investments [Line Items]
Investment	3,033,410 shares Series A Convertible Preferred Stock, convertible into 3,033,410 shares common stock at $1.00 per share (acquired 7-14-08 thru 11-18-10)	[2],[3],[6]	Warrants to purchase 1,269,833 shares of common stock at $1.00 per share, expiring 8-31-2021 (acquired 5-9-11 thru 8-31-11)	[2],[3],[6]
Cost	3,033,410	[2],[3]	0	[2],[3]
Value	1	[2],[3],[8]	0	[2],[3],[8]
CINATRA CLEAN TECHNOLOGIES, INC. [Member] | Investment Type 7 [Member]
Schedule of Investments [Line Items]
Investment	Warrants to purchase 1,436,499 shares of common stock at $1.00 per share, expiring 10-31-2027 (acquired 5-9-11 thru 10-19-12)	[2],[3],[6]
Cost	0	[2],[3]
Value	0	[2],[3],[8]
ENCORE WIRE CORPORATION [Member]
Schedule of Investments [Line Items]
Location	McKinney, Texas	[2],[3]	McKinney, Texas	[1],[2],[3],[4]
Description of company	Electric wire and cable for residential, commercial and industrial construction use.	[2],[3]	Electric wire and cable for residential, commercial and industrial construction use.	[1],[2],[3],[4]
Equity (in hundredths)	6.20%	[2],[3],[5]	16.90%	[1],[2],[3],[4],[5]
Investment	1,312,500 shares common stock (acquired 9-10-92 thru 10-15-98)	[2],[3],[6],[7]	4,086,750 shares common stock (acquired 7-16-92 thru 10-7-98)	[1],[2],[3],[4],[6],[7]
Cost	5,200,000	[2],[3]	5,800,000	[1],[2],[3],[4]
Value	39,768,750	[2],[3],[8]	121,458,210	[1],[2],[3],[4],[8]
EXTREME INTERNATIONAL, INC. [Member]
Schedule of Investments [Line Items]
Location			Sugar Land, Texas	[2],[3]
Description of company			Owns Bill Young Productions, Texas Video and Post, and Extreme and television commercials and corporate communications videos.	[2],[3]
Equity (in hundredths)			53.60%	[2],[3],[5]
Cost			3,325,875	[2],[3]
Value			10,162,000	[2],[3],[8]
EXTREME INTERNATIONAL, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment			13,035 shares Series A Common Stock (acquired 9-26-08 and 12-18-08)	[2],[3],[6]
Cost			325,875	[2],[3]
Value			714,000	[2],[3],[8]
EXTREME INTERNATIONAL, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment			39,359.18 shares Series C Convertible Preferred Stock, convertible into 157,437.72 shares of common stock at $25.00 per share (acquired 9-30-03)	[2],[3],[6]
Cost			2,625,000	[2],[3]
Value			8,626,000	[2],[3],[8]
EXTREME INTERNATIONAL, INC. [Member] | Investment Type 3 [Member]
Schedule of Investments [Line Items]
Investment			3,750 shares 8% Series A Convertible Preferred Stock, convertible into 15,000 shares of common stock at $25.00 per share (acquired 9-30-03)	[2],[3],[6]
Cost			375,000	[2],[3]
Value			822,000	[2],[3],[8]
HEELYS, INC. [Member]
Schedule of Investments [Line Items]
Location	Carrollton, Texas	[1],[2],[3],[9]	Carrollton, Texas	[1],[2],[3],[9]
Description of company	Heelys stealth skate shoes, equipment and apparel sold through sporting goods chains, department stores and footwear retailers.	[1],[2],[3],[9]	Heelys stealth skate shoes, equipment and apparel sold through sporting goods chains, department stores and footwear retailers.	[1],[2],[3],[9]
Equity (in hundredths)	31.10%	[1],[2],[3],[5],[9]	31.10%	[1],[2],[3],[5],[9]
Investment	9,317,310 shares common stock (acquired 5-26-00)	[1],[2],[3],[6],[7],[9]	9,317,310 shares common stock (acquired 5-26-00)	[1],[2],[3],[6],[7],[9]
Cost	102,490	[1],[2],[3],[9]	102,490	[1],[2],[3],[9]
Value	20,684,428	[1],[2],[3],[8],[9]	20,498,082	[1],[2],[3],[8],[9]
HOLOGIC, INC. [Member]
Schedule of Investments [Line Items]
Location	Bedford, Massachusetts	[1],[2],[3]	Bedford, Massachusetts	[1],[2],[3]
Description of company	Medical instruments including bone densitometers, mammography devices and digital radiography systems.	[1],[2],[3]	Medical instruments including bone densitometers, mammography devices and digital radiography systems.	[1],[2],[3]
Equity (in hundredths)	1.00%	[1],[2],[3],[5]	1.00%	[1],[2],[3],[5]
Investment	‡582,820 shares common stock (acquired 8-27-99)	[1],[2],[3],[6],[7]	632,820 shares common stock (acquired 8-27-99)	[1],[2],[3],[6],[7]
Cost	202,529	[1],[2],[3]	220,000	[1],[2],[3]
Value	11,662,286	[1],[2],[3],[8]	13,637,271	[1],[2],[3],[8]
iMEMORIES, INC. [Member]
Schedule of Investments [Line Items]
Location	Scottsdale, Arizona	[2],[3]	Scottsdale, Arizona	[2],[3]
Description of company	Enables online video and photo sharing and DVD creation for home movies recorded in analog and new digital format.	[2],[3]	Enables online video and photo sharing and DVD creation for home movies recorded in analog and new digital format.	[2],[3]
Equity (in hundredths)	23.00%	[2],[3],[5]	25.30%	[2],[3],[5]
Cost	5,386,479	[2],[3]	5,078,479	[2],[3]
Value	5,386,479	[2],[3],[8]	5,078,479	[2],[3],[8]
iMEMORIES, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	17,391,304 shares Series B Convertible Preferred Stock, convertible into 19,891,304 shares of common stock at $0.23 per share (acquired 7-10-09)	[2],[3],[6]	17,391,304 shares Series B Convertible Preferred Stock, convertible into 19,891,304 shares of common stock at $0.23 per share (acquired 7-10-09)	[2],[3],[6]
Cost	4,000,000	[2],[3]	4,000,000	[2],[3]
Value	4,000,000	[2],[3],[8]	4,000,000	[2],[3],[8]
iMEMORIES, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	4,684,967 shares Series C Convertible Preferred Stock, convertible into 4,684,967 shares of common stock at $0.23 per share (acquired 7-20-11)	[2],[3],[6]	4,684,967 shares Series C Convertible Preferred Stock, convertible into 4,684,967 shares of common stock at $0.23 per share (acquired 7-20-11)	[2],[3],[6]
Cost	1,078,479	[2],[3]	1,078,479	[2],[3]
Value	1,078,479	[2],[3],[8]	1,078,479	[2],[3],[8]
iMEMORIES, INC. [Member] | Investment Type 3 [Member]
Schedule of Investments [Line Items]
Investment	Warrants to purchase 2,500,000 shares of common stock at $0.12 per share, expiring 1-21-21(acquired 9-13-10 thru 1-21-11)	[2],[3],[6]	Warrants to purchase 2,500,000 shares of common stock at $0.12 per share, expiring 1-21-21(acquired 9-13-10 thru 1-21-11)	[2],[3],[6]
Cost	0	[2],[3]	0	[2],[3]
Value	0	[2],[3],[8]	0	[2],[3],[8]
iMEMORIES, INC. [Member] | Investment Type 4 [Member]
Schedule of Investments [Line Items]
Investment	10% convertible notes, $308,000 principal due 7-31-2014 (acquired 9-7-12)	[2],[3],[6]
Cost	308,000	[2],[3]
Value	308,000	[2],[3],[8]
INSTAWARES HOLDING COMPANY, LLC [Member]
Schedule of Investments [Line Items]
Location	Atlanta, Georgia	[2],[3]	Atlanta, Georgia	[2],[3]
Description of company	Provides services to the restaurant industry via its five subsidiary companies.	[2],[3]	Provides services to the restaurant industry via its five subsidiary companies.	[2],[3]
Equity (in hundredths)	4.50%	[2],[3],[5]	4.50%	[2],[3],[5]
Investment	3,846,154 Class D shares (acquired 5-20-11)	[2],[3],[6]	3,846,154 Class D shares (acquired 5-20-11)	[2],[3],[6]
Cost	5,000,000	[2],[3]	5,000,000	[2],[3]
Value	5,829,000	[2],[3],[8]	5,000,000	[2],[3],[8]
KBI BIOPHARMA, INC. [Member]
Schedule of Investments [Line Items]
Location	Durham, North Carolina	[2],[3]	Durham, North Carolina	[2],[3]
Description of company	Provides fully-integrated, outsourced drug development and bio-manufacturing services.	[2],[3]	Provides fully-integrated, outsourced drug development and bio-manufacturing services.	[2],[3]
Equity (in hundredths)	17.10%	[2],[3],[5]	17.10%	[2],[3],[5]
Investment			7,142,857 shares Series B-2 Convertible Preferred Stock, convertible into 10,204,082 shares of common stock at $0.49 per share (acquired 9-08-09)	[2],[3],[6]
Cost	5,000,000	[2],[3]	5,000,000	[2],[3]
Value	5,400,000	[2],[3],[8]	3,200,000	[2],[3],[8]
KBI BIOPHARMA, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	7,142,857 shares Series B-2 Convertible Preferred Stock, convertible into 7,142,857 shares of common stock at $0.49 per share (acquired 9-08-09)	[2],[3],[6]
Cost	5,000,000	[2],[3]
Value	5,400,000	[2],[3],[8]
KBI BIOPHARMA, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	Warrants to purchase 63,007 shares of preferred stock at $ 0.70 per share, acquired 1-26-2012	[2],[3],[6]
Cost	0	[2],[3]
Value	0	[2],[3],[8]
MEDIA RECOVERY, INC. [Member]
Schedule of Investments [Line Items]
Location	Dallas, Texas	[2],[3],[9]	Dallas, Texas	[2],[3],[9]
Description of company	Computer datacenter and office automation supplies and accessories; impact, tilt monitoring and temperature sensing devices to detect mishandling shipments; dunnage for protecting shipments.	[2],[3],[9]	Computer datacenter and office automation supplies and accessories; impact, tilt monitoring and temperature sensing devices to detect mishandling shipments; dunnage for protecting shipments.	[2],[3],[9]
Equity (in hundredths)	97.90%	[2],[3],[5],[9]	97.90%	[2],[3],[5],[9]
Cost	5,415,000	[2],[3]	5,415,000	[2],[3]
Value	13,300,000	[2],[3],[8]	18,700,000	[2],[3],[8]
MEDIA RECOVERY, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	800,000 shares Series A Convertible Preferred Stock, convertible into 800,000 shares of common stock at $1.00 per share (acquired 11-4-97)	[2],[3],[6],[9]	800,000 shares Series A Convertible Preferred Stock, convertible into 800,000 shares of common stock at $1.00 per share (acquired 11-4-97)	[2],[3],[6],[9]
Cost	800,000	[2],[3],[9]	800,000	[2],[3],[9]
Value	2,200,000	[2],[3],[8],[9]	3,100,000	[2],[3],[8],[9]
MEDIA RECOVERY, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	4,000,002 shares common stock (acquired 11-4-97)	[2],[3],[6]	4,000,002 shares common stock (acquired 11-4-97)	[2],[3],[6]
Cost	4,615,000	[2],[3]	4,615,000	[2],[3]
Value	11,100,000	[2],[3],[8]	15,600,000	[2],[3],[8]
PALLETONE, INC. [Member]
Schedule of Investments [Line Items]
Location	Bartow, Florida	[2],[3],[4]	Bartow, Florida	[2],[3],[4]
Description of company	Manufacturer of wooden pallets and pressure-treated lumber.	[2],[3],[4]	Manufacturer of wooden pallets and pressure-treated lumber.	[2],[3],[4]
Equity (in hundredths)	7.70%	[2],[3],[4],[5]	7.70%	[2],[3],[4],[5]
Cost	1,703,150	[2],[3]	1,703,150	[2],[3]
Value	1,600,002	[2],[3],[8]	2,000,002	[2],[3],[8]
PALLETONE, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	12.3% senior subordinated notes, $2,000,000 principal due 12-18-2015 (acquired 9-25-06)	[2],[3],[4],[6]	12.3% senior subordinated notes, $2,000,000 principal due 12-18- 2015 (acquired 9-25-06)	[2],[3],[4],[6]
Cost	1,553,150	[2],[3],[4]	1,553,150	[2],[3],[4]
Value	1,600,000	[2],[3],[4],[8]	2,000,000	[2],[3],[4],[8]
PALLETONE, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	150,000 shares common stock (acquired 10-18-01)	[2],[3],[6]	150,000 shares common stock (acquired 10-18-01)	[2],[3],[6]
Cost	150,000	[2],[3]	150,000	[2],[3]
Value	2	[2],[3],[8]	2	[2],[3],[8]
THE RECTORSEAL CORPORATION [Member]
Schedule of Investments [Line Items]
Location	Houston, Texas	[2],[3],[9]	Houston, Texas	[2],[3],[9]
Description of company	Specialty chemicals for plumbing, HVAC, electrical, construction, industrial, oil field and automotive applications; smoke containment systems for building fires; also owns 20% of The Whitmore Manufacturing Company.	[2],[3],[9]	Specialty chemicals for plumbing, HVAC, electrical, construction, industrial, oil field and automotive applications; smoke containment systems for building fires; also owns 20% of The Whitmore Manufacturing Company.	[2],[3],[9]
Equity (in hundredths)	100.00%	[2],[3],[5],[9]	100.00%	[2],[3],[5],[9]
Investment	27,907 shares common stock (acquired 1-5-73 and 3-31-73)	[2],[3],[6],[9]	27,907 shares common stock (acquired 1-5-73 and 3-31-73)	[2],[3],[6],[9]
Cost	52,600	[2],[3],[9]	52,600	[2],[3],[9]
Value	229,600,000	[2],[3],[8],[9]	166,300,000	[2],[3],[8],[9]
TCI HOLDINGS, INC. [Member]
Schedule of Investments [Line Items]
Location	Denver, Colorado	[2],[3]	Denver, Colorado	[2],[3]
Description of company	Cable television systems and microwave relay systems.	[2],[3]	Cable television systems and microwave relay systems.	[2],[3]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	21 shares 12% Series C Cumulative Compounding Preferred Stock (acquired 1-30-90)	[2],[3],[6]	21 shares 12% Series C Cumulative Compounding Preferred Stock (acquired 1-30-90)	[2],[3],[6]
Cost	0	[2],[3]	0	[2],[3]
Value	779,000	[2],[3],[8]	802,000	[2],[3],[8]
TITANLINER INC [Member]
Schedule of Investments [Line Items]
Location	Midland, Texas	[2],[3]
Description of company	Manufactures, installs and rents spill containment system for oilfield applications.	[2],[3]
Equity (in hundredths)	29.90%	[2],[3],[5]
Cost	5,950,000	[2],[3]
Value	5,950,000	[2],[3],[8]
TITANLINER INC [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	217,038 shares Series A Convertible Preferred Stock convertible into 217,038 shares of Series A preferred stock at $12.65 per share (acquired 6-29-2012)	[2],[3],[6]
Cost	3,203,000	[2],[3]
Value	3,203,000	[2],[3],[8]
TITANLINER INC [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	7% senior subordinated secured promissory note, due 6-30-2017 (acquired 6-29-2012)	[2],[3],[6]
Cost	2,747,000	[2],[3]
Value	2,747,000	[2],[3],[8]
TITANLINER INC [Member] | Investment Type 3 [Member]
Schedule of Investments [Line Items]
Investment	Warrants to purchase 122,239 shares of Series A preferred stock at $ 0.01 per share, expiring 1-26-2012	[2],[3],[6]
Cost	0	[2],[3]
Value	0	[2],[3],[8]
TRAX HOLDINGS, INC. [Member]
Schedule of Investments [Line Items]
Location	Scottsdale, Arizona	[2],[3]	Scottsdale, Arizona	[2],[3]
Description of company	Provides a comprehensive set of solutions to improve the transportation validation, accounting, payment and information management process.	[2],[3]	Provides a comprehensive set of solutions to improve the transportation validation, accounting, payment and information management process.	[2],[3]
Equity (in hundredths)	25.40%	[2],[3],[5]	29.40%	[2],[3],[5]
Cost	9,000,000	[2],[3]	8,200,000	[2],[3]
Value	19,400,000	[2],[3],[8]	9,800,000	[2],[3],[8]
TRAX HOLDINGS, INC. [Member] | Investment Type 1 [Member]
Schedule of Investments [Line Items]
Investment	475,430 shares Series B convertible Preferred Stock convertible into 475,430 common stock at $8.41 per share(acquired 12-5-12)	[2],[3],[6]	18% convertible promissory note, $3,200,000 principal due 9-17-2012 (acquired 4-6-11 thru 11-10-11)	[2],[3],[6]
Cost	4,000,000	[2],[3]	3,200,000	[2],[3]
Value	7,000,000	[2],[3],[8]	3,200,000	[2],[3],[8]
TRAX HOLDINGS, INC. [Member] | Investment Type 2 [Member]
Schedule of Investments [Line Items]
Investment	1,061,279 shares Series A Convertible Preferred Stock, convertible into 1,061,279 common stock at $4.64 per share (acquired 12-8-08 and 2-17-09)	[2],[3],[6]	1,061,279 shares Series A Convertible Preferred Stock, convertible into 1,061,279 common stock at $4.64 per share (acquired 12-8-08 and 2-17-09)	[2],[3],[6]
Cost	5,000,000	[2],[3]	5,000,000	[2],[3]
Value	12,400,000	[2],[3],[8]	6,600,000	[2],[3],[8]
VIA HOLDINGS, INC. [Member]
Schedule of Investments [Line Items]
Location			Sparks, Nevada	[2],[3]
Description of company			Designer, manufacturer and distributor of high-quality office seating.	[2],[3]
Equity (in hundredths)			3.20%	[2],[3],[5]
Investment			12,686 shares common stock (acquired 3-4-11 and 3-25-11)	[2],[3],[6]
Cost			4,926,290	[2],[3]
Value			2	[2],[3],[8]
WELLOGIX, INC. [Member]
Schedule of Investments [Line Items]
Location	Houston, Texas	[2],[3],[4]	Houston, Texas	[2],[3],[4]
Description of company	Developer and supporter of software used by the oil and gas industry.	[2],[3],[4]	Developer and supporter of software used by the oil and gas industry.	[2],[3],[4]
Equity (in hundredths)	19.10%	[2],[3],[4],[5]	19.10%	[2],[3],[4],[5]
Investment	4,788,371 shares Series A-1 Convertible Participating Preferred Stock, convertible into 4,788,371 shares of common stock at $1.0441 per share (acquired 8-19-05 thru 6-15-08)	[2],[3],[4],[6]	4,788,371 shares Series A-1 Convertible Participating Preferred Stock, convertible into 4,788,371 shares of common stock at $1.0441 per share (acquired 8-19-05 thru 6-15-08)	[2],[3],[4],[6]
Cost	5,000,000	[2],[3],[4]	5,000,000	[2],[3],[4]
Value	25,000	[2],[3],[4],[8]	25,000	[2],[3],[4],[8]
THE WHITMORE MANUFACTURING COMPANY [Member]
Schedule of Investments [Line Items]
Location	Rockwall, Texas	[2],[3],[9]	Rockwall, Texas	[2],[3],[9]
Description of company	Specialized surface mining, railroad and industrial lubricants; coatings for automobiles and primary metals; fluid contamination control devices.	[2],[3],[9]	Specialized surface mining, railroad and industrial lubricants; coatings for automobiles and primary metals; fluid contamination control devices.	[2],[3],[9]
Equity (in hundredths)	80.00%	[2],[3],[5],[9]	80.00%	[2],[3],[5],[9]
Investment	80 shares common stock (acquired 8-31-79)	[2],[3],[6],[9]	80 shares common stock (acquired 8-31-79)	[2],[3],[6],[9]
Cost	1,600,000	[2],[3],[9]	1,600,000	[2],[3],[9]
Value	71,400,000	[2],[3],[8],[9]	67,200,000	[2],[3],[8],[9]
Ballast Point Ventures II, L.P. [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	Ballast Point Ventures II, L.P. 2.2% limited partnership interest (acquired 8-4-08 thru 6-18-10)	[2],[3],[6]	Ballast Point Ventures II, L.P. 2.2% limited partnership interest (acquired 8-4-08 thru 6-18-10)	[2],[3],[6]
Cost	1,359,790	[2],[3]	1,725,000	[2],[3]
Value	1,359,000	[2],[3],[8]	1,551,000	[2],[3],[8]
BankCap Partners Fund I, L.P. [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	BankCap Partners Fund I, L.P. 5.5% limited partnership interest (acquired 7-14-06 thru 11-30-11)	[2],[3],[6]	BankCap Partners Fund I, L.P. 5.5% limited partnership interest (acquired 7-14-06 thru 11-30-11)	[2],[3],[6]
Cost	5,897,276	[2],[3]	5,808,470	[2],[3]
Value	5,016,000	[2],[3],[8]	5,012,000	[2],[3],[8]
CapitalSouth Partners Fund III, L.P. [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	CapitalSouth Partners Fund III, L.P. 1.9% limited partnership interest (acquired 1-22-08 and 11-16-11)	[2],[3],[6]	CapitalSouth Partners Fund III, L.P. 1.9% limited partnership interest (acquired 1-22-08 and 11-16-11)	[2],[3],[6]
Cost	1,331,256	[2],[3]	1,331,256	[2],[3]
Value	1,816,000	[2],[3],[8]	1,438,000	[2],[3],[8]
CapStar Holdings Corporation [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	100.00%	[2],[3],[5],[9]	100.00%	[2],[3],[5],[9]
Investment	CapStar Holdings Corporation 500 shares common stock (acquired 6-10-10); 1,000,000 shares preferred stock (acquired 12-17-12)	[2],[3],[6],[9]	CapStar Holdings Corporation 500 shares common stock (acquired 6-10-10)	[2],[3],[6],[9]
Cost	4,703,619	[2],[3],[9]	3,703,619	[2],[3],[9]
Value	6,674,000	[2],[3],[8],[9]	5,338,000	[2],[3],[8],[9]
Diamond State Ventures, L.P. [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	Diamond State Ventures, L.P. 1.4% limited partnership interest (acquired 10-12-99 thru 8-26-05)	[2],[3],[6]	Diamond State Ventures, L.P. 1.4% limited partnership interest (acquired 10-12-99 thru 8-26-05)	[2],[3],[6]
Cost	0	[2],[3]	76,000	[2],[3]
Value	96,000	[2],[3],[8]	184,000	[2],[3],[8]
Discovery Alliance, LLC [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5],[9]	0.00%	[2],[3],[5],[9]
Investment	Discovery Alliance, LLC 90.0% limited liability company (acquired 9-12-08 thru 10-20-11)	[2],[3],[6],[9]	Discovery Alliance, LLC 90.0% limited liability company (acquired 9-12-08 thru 10-20-11)	[2],[3],[6],[9]
Cost	1,315,000	[2],[3],[9]	1,180,000	[2],[3],[9]
Value	1,167,000	[2],[3],[8],[9]	1,280,000	[2],[3],[8],[9]
First Capital Group of Texas III, L.P. [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	First Capital Group of Texas III, L.P. 3.0% limited partnership interest (acquired 12-26-00 thru 8-12-05)	[2],[3],[6]	First Capital Group of Texas III, L.P. 3.0% limited partnership interest (acquired 12-26-00 thru 8-12-05)	[2],[3],[6]
Cost	778,895	[2],[3]	778,895	[2],[3]
Value	164,000	[2],[3],[8]	662,000	[2],[3],[8]
Humac Company [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	100.00%	[2],[3],[5],[9]	100.00%	[2],[3],[5],[9]
Investment	Humac Company 1,041,000 shares common stock (acquired 1-31-75 and 12-31-75)	[2],[3],[6],[9]	Humac Company 1,041,000 shares common stock (acquired 1-31-75 and 12-31-75)	[2],[3],[6],[9]
Cost	0	[2],[3],[9]	0	[2],[3],[9]
Value	169,000	[2],[3],[8],[9]	159,000	[2],[3],[8],[9]
North American Energy Partners, Inc [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[1],[2],[3],[5]
Investment	North American Energy Partners, Inc. 77,194 shares common stock (acquired 8-20-12)	[1],[2],[3],[6]
Cost	236,986	[1],[2],[3]
Value	262,460	[1],[2],[3],[8]
STARTech Seed Fund I [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)			0.00%	[2],[3],[5]
Investment			STARTech Seed Fund I 12.1% limited partnership interest (acquired 4-17-98 thru 1-5-00)	[2],[3],[6]
Cost			178,066	[2],[3]
Value			39,000	[2],[3],[8]
STARTech Seed Fund II [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)	0.00%	[2],[3],[5]	0.00%	[2],[3],[5]
Investment	STARTech Seed Fund II 3.2% limited partnership interest (acquired 4-28-00 thru 2-23-05)	[2],[3],[6]	STARTech Seed Fund II 3.2% limited partnership interest (acquired 4-28-00 thru 2-23-05)	[2],[3],[6]
Cost	754,327	[2],[3]	843,891	[2],[3]
Value	364,000	[2],[3],[8]	371,000	[2],[3],[8]
Sterling Group Partners I, L.P. [Member]
Schedule of Investments [Line Items]
Equity (in hundredths)			0.00%	[2],[3],[5]
Investment			Sterling Group Partners I, L.P. 1.7% limited partnership interest (acquired 4-20-01 thru 1-24-05)	[2],[3],[6]
Cost			1,064,042	[2],[3]
Value			$ 511,000	[2],[3],[8]

[1] Publicly-owned company

[2] Agreements between certain issuers and the Company provide that the issuer will bear substantially all costs in connection with the Company disposing such common stock, including those costs involved in registration under the Securities Act of 1933, but excluding underwriting discounts and commissions. These agreements cover common stock owned at December 31, 2012 and common stock which may be acquired thereafter through the exercise of warrants and conversion of debentures and preferred stock. They apply to restricted securities of all issuers in the investment portfolio of the Company except securities of the following issuers which are not obligated to bear registration costs: Humac Company and The Whitmore Manufacturing Company.

[3] The descriptions of the companies and ownership percentages shown in the Consolidated Schedule of Investments were obtained from published reports and other sources believed to be reliable. Acquisition dates indicated are the dates specific securities were acquired, which may differ from the original investment dates. Certain securities were received in exchange for or upon conversion or exercise of other securities previously acquired.

[4] Affiliated investment

[5] The percentages in the "Equity" column express equity interests held by Capital Southwest Corporation and Capital Southwest Venture Corporation (together, the "Company") in each issuer. Each percentage represents the amount of the issuer's common stock the Company owns or can acquire as a percentage of the issuer's total outstanding common stock, plus stock reserved for all warrants, convertible securities and employee stock options.

[6] Unrestricted securities (indicated by ‡) are freely marketable securities having readily available market quotations. All other securities are restricted securities, which are subject to one or more restrictions on resale and are not freely marketable. At December 31, 2012 and March 31, 2012, restricted securities represented approximately 70.1% and 56.9% of the value of the consolidated investment portfolio, respectively. Our investments are carried at fair value in accordance with the Investment Company Act of 1940 (the "1940 Act") and FASB Accounting Standards Codification (ASC) 820, Fair Value Measurements and Disclosures. In accordance with the 1940 Act, unrestricted minority-owned publicly traded securities, for which the market quotations are readily available, are valued at the closing sale price for the NYSE listed securities and the lower of the closing bid price or the last sale price for NASDAQ securities on the valuation date; other privately held securities are valued as determined in good faith by our Board of Directors. ASC 820 defines fair value in terms of the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (the "exit price") and excludes transaction costs. Under ASC 820, the fair value measurement also assumes that the transaction to sell an asset occurs in the principal market for the asset or, in the absence of a principal market, the most advantageous market for the asset. The principal market is the market in which the reporting entity would sell or transfer the asset with the greatest volume and level of activity for the asset. In determining the principal market for an asset or liability under ASC 820, it is assumed that the reporting entity has access to the market as of the measurement date.

[7] Unrestricted securities as define in Note (a)

[8] Debt Securities are generally valued on the basis of the price the security would command in order to provide a yield-to-maturity equivalent to the present yield of comparable debt instruments of similar quality. Issuers whose debt securities are judged to be of poor quality and doubtful collectability may instead be valued by assigning percentage discounts commensurate with the quality of such debt securities. Debt securities may also be valued based on the resulting value from the sale of the business at the estimated fair market value. Partnership Interests, Preferred Equity and Common Equity, including unrestricted marketable securities, are valued at the closing sale price for the NYSE listed securities and the lower of the closing bid price or the last sale price for NASDAQ securities on the valuation date. For those without a principal market, our Board of Directors considers the financial condition and operating results of the issuer; the long-term potential of the business of the issuer; the market for and recent sales prices of the issuer's securities; the values of similar securities issued by companies in similar businesses; and the proportion of the issuer's securities owned by the Company. Investments in certain entities that calculate net asset value per share (or its equivalent) and for which fair market value is not readily determinable are valued using the net asset value per share (or its equivalent, such as member units or ownership interest in partners' capital to which a proportionate share of net assets is attributed) of the investment. Equity Warrants are valued on the basis of the Black-Scholes model which defines the market value of a warrant in relation to the market price of its common stock, share price volatility, and time to maturity.

[9] Control investment