Earnings Per Common Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net income attributable to Michael Baker Corporation
Net income from continuing operations before noncontrolling interests	$ 838	$ 7,295	$ 4,888	$ 13,631
Less: Income attributable to noncontrolling interests	179	178	585	814
Net income from continuing operations attributable to Michael Baker Corporation	659	7,117	4,303	12,817
Net income from discontinued operations, net of tax	322	116	822	101
Net income attributable to Michael Baker Corporation	$ 981	$ 7,233	$ 5,125	$ 12,918
Basic:
Weighted average shares outstanding	9,390	9,324	9,375	9,284
Earnings per share:
Continuing operations	$ 0.07	$ 0.76	$ 0.46	$ 1.38
Discontinued operations	$ 0.04	$ 0.01	$ 0.09	$ 0.01
Total	$ 0.11	$ 0.77	$ 0.55	$ 1.39
Effect of dilutive securities -
Contingently issuable shares and stock options	256	10	240	22
Weighted average shares outstanding	9,646	9,334	9,615	9,306
Earnings per share:
Continuing operations	$ 0.07	$ 0.76	$ 0.45	$ 1.38
Discontinued operations	$ 0.03	$ 0.01	$ 0.08	$ 0.01
Total	$ 0.10	$ 0.77	$ 0.53	$ 1.39