Employee Retirement Plans (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Benefit Plans Disclosures [Line Items]
Plan assets expected to be returned	$ 0
Prior service cost included in AOCL	100,000
Prior service cost included in AOCL, net of tax	100,000
Unrecognized actuarial losses included in AOCL	68,300,000
Unrecognized actuarial losses included in AOCL, net of tax	42,900,000
Actuarial loss expected to be recognized in net periodic pension cost	1,300,000
Actuarial loss expected to be recognized in net periodic pension cost, net of tax	800,000
Expected employer contributions to defined benefit plans next year	15,300,000
Actual employer contributions to defined benefit plans	18,900,000	17,300,000
Expected employer contributions to 401(k) plans and Supplemental Profit Sharing Plan next year	12,500,000
Actual employer contributions to 401(k) plans and Supplemental Profit Sharing Plan	$ 11,700,000	$ 9,300,000	$ 8,200,000
Minimum
Schedule of Benefit Plans Disclosures [Line Items]
Company contributions to the Profit Sharing Plan as a percentage of eligible compensation based on service	1.00%
Maximum
Schedule of Benefit Plans Disclosures [Line Items]
Company contributions to the Profit Sharing Plan as a percentage of eligible compensation based on service	3.00%