Derivative Financial Instruments (Details) (USD $)	12 Months Ended						1 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012 agreement	Jan. 01, 2012	Aug. 31, 2010	Dec. 31, 2013 Other Liabilities	Dec. 31, 2012 Other Liabilities	Oct. 31, 2013 Interest Rate Swap	Dec. 31, 2013 Interest Rate Swap	Dec. 31, 2012 Fair Value Hedging Interest Rate Swap	Jan. 01, 2012 Fair Value Hedging Interest Rate Swap	Dec. 31, 2012 7.75% Senior Notes Interest Rate Swap	Dec. 31, 2013 Senior Notes 7.75% Senior Notes	Oct. 03, 2013 Senior Notes 7.75% Senior Notes
Interest Rate Swaps [Abstract]
Stated interest rate				8.47%								7.75%
Number of Interest Rate Swap Agreements		4
Notional amount								$ 50,900,000			$ 100,000,000
Gains (loss) recongized and recorded in earnings related to fair value hedge	(3,974,000)	0	0						(1,200,000)	4,100,000
Fair value of the swap assets included as Other Non-Current Assests		6,200,000	7,400,000
Proceeds from Settlement of Notional Amount Derivative							5,100,000
Proceeds from Settlement of Notional Amount Derivative, Accrued Interest							1,100,000
Repurchased face amount													209,100,000
Fixed interest rate on cash flow interest rate derivative	9.70%
Net unrealized loss recognized in the periods and recorded in accumulated other comprehensive income, net of tax		(500,000)	(1,200,000)
Value of swap liability					$ 400,000	$ 700,000