XML 42 R30.htm IDEA: XBRL DOCUMENT v3.5.0.2
Earnings per Share (Detail) - shares
3 Months Ended 6 Months Ended
Sep. 01, 2015
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]          
Shares purchased in Stock Repurchase Agreement 950,000        
Anti-dilutive securities excluded from computation of earnings per share (in shares)       0 0
Dilutive securities (in shares)   0 4,000 0 4,000
Incremental shares from potential dilutive securities   0 795 0 755
ICP [Member]          
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]          
Equity method ownership percentage (percent)   30.00%   30.00%  
ICP [Member] | SEACOR Holdings, Inc. [Member]          
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]          
Equity method ownership percentage (percent)   70.00%   70.00%  
Restricted Stock [Member]          
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]          
Restricted stock (in shares)       128,500 248,100