Real Estate and Accumulated Depreciation (Details Textual) (Buildings and Improvements [Member])	12 Months Ended
Dec. 31, 2011 Y
Buildings and Improvements [Member]
Real Estate and Accumulated Depreciation (Textual) [Abstract]
Minimum estimated useful life of buildings and improvements	24
Maximum estimated useful life of buildings and improvements	40

The maximum useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLifeMaximum
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration