Summary of Significant Accounting Policies (Details Textual) (USD $)	6 Months Ended
Jun. 30, 2012
Summary of Significant Accounting Policies (Textual) [Abstract]
Dividends paid or accrued per Series C Preferred Share	$ 0.40625
Preferred Stock, Liquidation Preference Percentage	6.50%

Aggregate dividends paid during the period for each share of preferred stock outstanding.

No definition available.

Name:	us-gaap_PreferredStockDividendsPerShareCashPaid
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration