CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) [Abstract]
Common dividends declared per share (in dollars per share)	$ 0.30	$ 0.30	$ 1.30
Preferred dividends declared per share (in dollars per share)	$ 2.00	$ 2.00	$ 2.00
Shares issued in lieu of Directors' fees (in shares)	17,636	15,214	3,921
Issuance of common stock (in shares)	0	0	6,250,000
Issuance of preferred stock (in shares)	1,046,400	1,974,896	0
Shares of restricted stock withheld to satisfy tax withholding obligations on vesting of restricted stock (in shares)	19,133	42,618	3,954
Shares of deferred incentive share units withheld to satisfy tax withholding obligations on vesting of DISUs (in shares)	1,656	1,465	860
Distribution of shares of common stock from deferred compensation plan (in shares)	51,827	17,125	15,125
Contribution of shares of common stock to deferred compensation plan (in shares)	2,061	4,004	1,080