Consolidated Balance Sheets (Parentheticals) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Redeemable Convertible Preferred Stock Series B [Member]
Preferred stock, par or stated value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock liquidation preference value (in dollars per share)	$ 1,000	$ 1,000
Preferred stock shares authorized (in shares)	40,000	40,000
Preferred stock shares issued (in shares)	16,600	0
Preferred stock shares outstanding (in shares)	16,600	0
Convertible Series AA Preferred Stock [Member]
Preferred stock, par or stated value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock liquidation preference value (in dollars per share)	$ 25	$ 25
Preferred stock shares authorized (in shares)	1,000,000	1,000,000
Preferred stock shares issued (in shares)	0	0
Preferred stock shares outstanding (in shares)	0	0
Preferred stock dividend rate percentage (in hundredths)	7.00%
Redeemable Convertible Series 6.3% Preferred Stock [Member]
Preferred stock, par or stated value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock liquidation preference value (in dollars per share)	$ 1,000	$ 1,000
Preferred stock shares authorized (in shares)	10,000	10,000
Preferred stock shares issued (in shares)	0	1,649
Preferred stock shares outstanding (in shares)	0	1,649
Preferred stock dividend rate percentage (in hundredths)	6.30%	6.30%
Common Class A [Member]
Common stock, par or stated value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock shares issued (in shares)	16,887,377	16,473,674
Common stock shares outstanding (in shares)	16,887,377	16,473,674
Common Class B [Member]
Common stock, par or stated value (in dollars per share)	$ 0.01
Common stock, shares authorized (in shares)	1,000

Face amount or stated value per share of common stock.

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