Condensed Consolidated Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net income	$ 42,981	$ 46,161	$ 92,005	$ 88,533
Post-retirement benefit obligation	23	17	338	(191)
Comprehensive Income	43,004	46,178	92,343	88,342
Comprehensive income allocated to participating securities	(383)	(684)	(879)	(1,268)
Comprehensive Income allocated to common stockholders	$ 42,621	$ 45,494	$ 91,464	$ 87,074