Consolidated Statement of Shareholders' Equity Statement (USD $) In Thousands	Total	Common Stock [Member]	Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]
Balances at Dec. 31, 2012	$ 303,580	$ 390	$ 634,800	$ (370,870)	$ 39,260
Net income attributable to TriMas Corporation	68,700			68,700
Other comprehensive loss	(7,990)				(7,990)
Proceeds from sale of common stock in connection with the Company's equity offering, net of issuance costs	174,720	50	174,670
Shares surrendered upon vesting of options and restricted stock awards to cover tax obligations	(3,930)		(3,930)
Stock option exercises and restricted stock vesting	1,350	10	1,340
Excess tax benefits from stock based compensation	1,280		1,280
Non-cash compensation expense	7,110		7,110
Balances at Sep. 30, 2013	$ 544,820	$ 450	$ 815,270	$ (302,170)	$ 31,270