Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Accounting Policies Earning Per Common Share (Details)

v3.5.0.2
Basis of Presentation and Accounting Policies Earning Per Common Share (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Net Income (Loss) attributable to SEACOR Holdings Inc. $ (39,803,000) $ 6,965,000 $ (122,148,000) $ (11,917,000)
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units 0 0 0 0
Dilutive Securities, Effect on Basic Earnings Per Share, Dilutive Convertible Securities 0 0 0 0
Net Income (Loss) Available to Common Stockholders, Diluted $ (39,803,000) $ 6,965,000 $ (122,148,000) $ (11,917,000)
Weighted Average Number of Shares Outstanding, Basic 16,943,647 17,294,927 16,896,751 17,616,035
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements 0 266,180 0 0
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities 0 0 0 0
Weighted Average Number of Shares Outstanding, Diluted 16,943,647 17,561,107 16,896,751 17,616,035
Basic Earnings (Loss) Per Common Share of SEACOR Holdings Inc. $ (2.35) $ 0.40 $ (7.23) $ (0.68)
Diluted Earnings (Loss) Per Common Share of SEACOR Holdings Inc. $ (2.35) $ 0.40 $ (7.23) $ (0.68)
Stock Compensation Plan [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 2,041,652 846,934 2,041,652 2,038,450
Two Point Five Percentage Convertible Notes [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 2,382,626   4,200,525  
Three Point Zero Percentage Convertible Notes [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 1,825,326   1,825,326  
Three Point Seven Five Percentage Convertible Notes [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 2,243,500      
Three Point Seven Five Percentage Convertible Notes [Member]        
Debt Instrument, Interest Rate, Stated Percentage 3.75%   3.75%  
Three Point Seven Five Percentage Convertible Notes [Member] | Convertible Debt Securities [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount     2,243,500  
Three Point Zero Percentage Convertible Notes [Member]        
Debt Instrument, Interest Rate, Stated Percentage 3.00%   3.00%  
Three Point Zero Percentage Convertible Notes [Member] | Convertible Debt Securities [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount     1,825,326  
Two Point Five Percentage Convertible Notes [Member]        
Debt Instrument, Interest Rate, Stated Percentage 2.50%   2.50%  
Two Point Five Percentage Convertible Notes [Member] | Convertible Debt Securities [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount     2,910,688