Consolidated balance sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Preferred stock, shares authorized	600,000us-gaap_PreferredStockSharesAuthorized	600,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, shares outstanding	1,423,916us-gaap_CommonStockSharesOutstanding	1,422,160us-gaap_CommonStockSharesOutstanding
Class A Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	364,896	70,117
Common stock, shares outstanding	364,896	70,117
Class B Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	344,859	357,882
Common stock, shares outstanding	344,859	357,882
Class C Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	209,882	209,882
Common stock, shares outstanding	209,882	209,882
Class D Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	0	279,999
Common stock, shares outstanding	0	279,999
Class E Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	504,276	504,276
Common stock, shares outstanding	504,276	504,276
Class F Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	1	1
Common stock, shares issued	1	1
Common stock, shares outstanding	1	1
Class G Common Stock [Member]
Common stock, par value	0.01	0.01
Common stock, shares authorized	3	3
Common stock, shares issued	2	3
Common stock, shares outstanding	2	3

Face amount or stated value per share of common stock.

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