Employee Benefit Plans (Details 4) (Employee Pension Plans, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Pension Plans
Change in Fair Value of Plan Assets
Balance at beginning of year	$ 66,137,000	$ 62,105,000
Actual return on plan assets	8,545,000	3,621,000
Company contribution	3,478,000	5,780,000
Benefit payments	(5,543,000)	(5,369,000)
Balance at end of year	72,617,000	66,137,000	62,105,000
Change in Benefit Obligations
Balance at beginning of year	105,320,000	100,656,000
Interest cost	3,710,000	4,011,000	4,526,000
Assumption change loss	(9,627,000)	6,031,000
Actuarial (gain) loss	1,318,000	(9,000)
Benefit payments	(5,543,000)	(5,369,000)
Balance at end of year	95,178,000	105,320,000	100,656,000
Funded Status
Funded status at end of year	(22,561,000)	(39,183,000)
Amounts recognized in Consolidated Balance Sheets consist of:
Current liabilities	(194,000)	(187,000)
Long-term liabilities	(22,367,000)	(38,996,000)
Net amount recognized in Consolidated Balance Sheets	(22,561,000)	(39,183,000)
Amounts not yet reflected in net periodic benefit cost and included in accumulated other comprehensive loss:
Net actuarial loss	(42,261,000)	(60,935,000)
Accumulated other comprehensive loss	(42,261,000)	(60,935,000)		(44,500,000)
Cumulative Company contributions in excess of net periodic benefit cost	19,700,000	21,752,000
Net amount recognized in Consolidated Balance Sheets	(22,561,000)	(39,183,000)
Other comprehensive gain (loss)	18,700,000	(1,700,000)	(14,800,000)
Amount to be amortized from other comprehensive loss into cost in 2014	$ 4,300,000
Actuarial assumptions used to determine benefit obligation
Discount rate (as a percent)	4.47%	3.58%
Measurement date	December 31	December 31
Expected return on assets (as a percent)	6.75%	7.00%	7.50%
Expected return on assets in 2014 (as a percent)	6.75%