Shareholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Common Stock [Member] Insignificant Acquisitions [Member]	Sep. 30, 2013 Common Stock [Member] Insignificant Acquisitions [Member]	Sep. 30, 2012 Common Stock [Member] Insignificant Acquisitions [Member]	Dec. 31, 2012 Common Stock [Member] Insignificant Acquisitions [Member]	Dec. 31, 2011 Common Stock [Member] Insignificant Acquisitions [Member]
Class of Stock [Line Items]
Common stock issued during the period (in shares)					400,000	40,225	1,014,697
Common stock subscribed and issued (in shares)								0	53,547
Amount of common stock issued for acquisitions			$ (726)		$ 885	$ 124	$ 5,561
Shares released from escrow					297,973
Common stock subscribed and cancelled (in shares)					122,292
General and administrative	$ 9,654	$ 7,783	$ 25,567	$ 23,822	$ 1,345