Acquisitions - Redeemable Noncontrolling Interest (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		4 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Feb. 23, 2012 Fair Value, Inputs, Level 3 [Member]
Redeemable Noncontrolling Interest [Line Items]
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value							$ 25,630
Distributions to noncontrolling interests			(410)
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	510	0	270	270	0
Redeemable noncontrolling interest, ending balance	$ 25,490		$ 25,490	$ 25,490		$ 0