Information About Segments of Business Reconciliation of Assets from Segment to Consolidated (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Segment Reporting, Asset Reconciling Item
Assets	$ 15,875.2		$ 16,050.4	[1]
General Insurance Group [Member]
Segment Reporting, Asset Reconciling Item
Assets	12,510.2		12,311.2	[1]
RFIG Run-off Business [Member]
Segment Reporting, Asset Reconciling Item
Assets	2,090.2		2,100.7	[1]
Title Insurance Segment [Member]
Segment Reporting, Asset Reconciling Item
Assets	993.5		956.2	[1]
All Other Segments [Member]
Segment Reporting, Asset Reconciling Item
Assets	706.3	[2]	973.4	[1],[2]
Intersegment Elimination [Member]
Segment Reporting, Asset Reconciling Item
Assets	$ (425.1)		$ (291.2)	[1]

[1] (c) 2011 segment information for General Insurance and RFIG Run-off Business has been reclassified to conform to the 2012 presentation.

[2] (b)Represents amounts for Old Republic's holding company parent, minor corporate services subsidiaries, and a small life and health insurance operation.