Interest Rate Swap (Notes)	9 Months Ended
Sep. 30, 2014
Interest Rate Swap [Abstract]
Interest Rate Swap [Text Block]	Interest Rate Swap Agreements In May 2011, the Company entered into $250,000 notional amount of interest rate swap agreements (2011 Swap Agreements) that are scheduled to expire June 1, 2017. Under the 2011 Swap Agreements, the Company receives a fixed rate of 5.75% and pays a variable rate of the three month LIBOR plus 3.50% adjusted quarterly, which allows the Company to adjust $250,000 of its senior notes to a floating rate. At September 30, 2014, the variable rate was 3.74%. In April 2014, the Company entered into $300,000 notional amount of interest rate swap agreements (2014 Swap Agreements) that are scheduled to expire May 15, 2022. Under the 2014 Swap Agreements, the Company receives a fixed rate of 4.75% and pays a variable rate of the three month LIBOR plus 2.27% adjusted quarterly, which allows the Company to adjust $300,000 of its senior notes to a floating rate. At September 30, 2014, the variable rate was 2.51%. The 2011 and 2014 Swap Agreements are formally designated and qualify as fair value hedges. The 2011 and 2014 Swap Agreements are recorded at fair value in the Consolidated Balance Sheet in other assets or other liabilities. Gains and losses due to changes in fair value of the interest rate swap agreements completely offset changes in the fair value of the hedged portion of the underlying debt. Therefore, no gain or loss has been recognized due to hedge ineffectiveness. Offsetting changes in fair value of both the interest rate swap agreements and the hedged portion of the underlying debt both were recognized in interest expense in the Consolidated Statement of Operations. The Company does not hold or issue any derivative instrument for trading or speculative purposes. The fair values of the 2011 Swap Agreements as of September 30, 2014 were an asset of approximately $6,796 and are included in other long term assets in the Consolidated Balance Sheet. The fair values of the 2014 Swap Agreements as of September 30, 2014 were a liability of approximately $1,250 and are included in other long term liabilities in the Consolidated Balance Sheet. The fair value of the 2011 and 2014 Swap Agreements excludes accrued interest and takes into consideration current interest rates and current likelihood of the swap counterparties' compliance with its contractual obligations.

Interest Rate Swap Agreements

In May 2011, the Company entered into $250,000 notional amount of interest rate swap agreements (2011 Swap Agreements) that are scheduled to expire June 1, 2017. Under the 2011 Swap Agreements, the Company receives a fixed rate of 5.75% and pays a variable rate of the three month LIBOR plus 3.50% adjusted quarterly, which allows the Company to adjust $250,000 of its senior notes to a floating rate. At September 30, 2014, the variable rate was 3.74%.

In April 2014, the Company entered into $300,000 notional amount of interest rate swap agreements (2014 Swap Agreements) that are scheduled to expire May 15, 2022. Under the 2014 Swap Agreements, the Company receives a fixed rate of 4.75% and pays a variable rate of the three month LIBOR plus 2.27% adjusted quarterly, which allows the Company to adjust $300,000 of its senior notes to a floating rate. At September 30, 2014, the variable rate was 2.51%.

The 2011 and 2014 Swap Agreements are formally designated and qualify as fair value hedges. The 2011 and 2014 Swap Agreements are recorded at fair value in the Consolidated Balance Sheet in other assets or other liabilities. Gains and losses due to changes in fair value of the interest rate swap agreements completely offset changes in the fair value of the hedged portion of the underlying debt. Therefore, no gain or loss has been recognized due to hedge ineffectiveness. Offsetting changes in fair value of both the interest rate swap agreements and the hedged portion of the underlying debt both were recognized in interest expense in the Consolidated Statement of Operations. The Company does not hold or issue any derivative instrument for trading or speculative purposes.

The fair values of the 2011 Swap Agreements as of September 30, 2014 were an asset of approximately $6,796 and are included in other long term assets in the Consolidated Balance Sheet. The fair values of the 2014 Swap Agreements as of September 30, 2014 were a liability of approximately $1,250 and are included in other long term liabilities in the Consolidated Balance Sheet.

The fair value of the 2011 and 2014 Swap Agreements excludes accrued interest and takes into consideration current interest rates and current likelihood of the swap counterparties' compliance with its contractual obligations.