Revenues, detail (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues [Abstract]
Time charter revenue	$ 191,977	$ 146,533	$ 108,487
Voyage charter revenue	1,113	1,095	0
Other income	8,458	6,412	5,472
Total	$ 201,548	$ 154,040	$ 113,959

Revenues generated from charterers for the time or voyage charter hire of vessels.Revenues from time charter may also include ballast bonus, which is an amount paid by the charterer for repositioning the vessel at the charterers disposal, and other miscellaneous revenues from vessel operations.

No definition available.

Name:	sb_TimeCharterAndVoyageRevenue
Namespace Prefix:	sb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration