Equity (Details)	12 Months Ended			12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 Common Stock Item	Dec. 31, 2013 Employee Options	Dec. 31, 2013 Partnership agreement of Operating Partnership Item	Dec. 31, 2013 Class B common stock Item	Dec. 31, 2012 Class B common stock	Dec. 31, 2013 Class B common stock Maximum Item
Equity
Minimum number of additional classes or series of common stock that the Board is authorized to reclassify from excess common stock	1
Equity
Number of votes entitled per share to holders of common stock		1
Number of members of board of directors elected under entitlement of right							4
Common stock, shares outstanding					8,000	8,000
Number of voting trusts which are subject to outstanding shares common stock					2
Common stock, shares issued			1,567	596,051	8,000	8,000
The number of limited partners who received common stock in exchange for an equal number of units, during the period.				11