Employee Pension Plans (Details) (Defined benefit pension plan, USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Defined benefit pension plan
Summary of net periodic benefit cost
Interest cost	$ 1,030,000	$ 916,000
Expected return on plan assets	(1,192,000)	(1,120,000)
Amortization of net loss	1,077,000	1,544,000
Net periodic benefit cost	915,000	1,340,000
Company contribution	600,000
Expected contributions remainder of current fiscal year	$ 2,800,000