Shareholders' Equity Schedule of Additional Paid-In Capital (Tables)

3 Months Ended

Mar. 31, 2013

Additional Paid in Capital [Abstract]

Schedule of Additional Paid in Capital [Table Text Block]

Additional Paid-In Capital

The following table presents a rollforward of the Company's changes in additional paid-in capital for the periods indicated:

	Three Months Ended
	March 31,
	2013			2012
Balance as of beginning of period	$	759,214		$	634,683
Common stock issuances:
DRIP issuances	3,224			37
ATM issuances	1,954			3,674
Secondary offering	—			119,859
Adjustments related to tax withholding for share-based compensation	(545		)	—
Amortization of restricted stock, net of additional grants	455			369
Capitalized expenses	(30		)	(119		)
Balance as of end of period	$	764,272		$	758,503