Earnings Per Common Share (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net Income attributed to:
Net income	$ 15,300	$ 9,413	$ 42,270	$ 33,089
Common Shares
Net Income attributed to:
Net income	15,300	9,413	42,270	33,066
Participating restricted common stock
Net Income attributed to:
Net income				$ 23