Debt	9 Months Ended
Sep. 30, 2015
Debt Disclosure [Abstract]
Debt	Debt During the nine months ended September 30, 2015, we made principal payments of $25.0 million on our five-year term loan due October 2018, and $4.9 million on our seven-year term loan, due October 2020. On September 5, 2014, we issued $400.0 million of 3.65% fixed-rate senior notes due September 15, 2024, through a registered public offering. We used the proceeds of this offering and other cash from operations to repay $589.9 million of debt during the nine months ended September 30, 2014. For the nine months ended September 30, 2015 and 2014, cash payments for interest were $58.6 million and $50.0 million, respectively. Included in interest expense, net, are amortization of treasury lock settlements and amortization of financing costs. For both the three months ended September 30, 2015 and 2014, amortization of treasury lock settlements was $1.4 million, and for both the nine months ended September 30, 2015 and 2014, amortization of treasury lock settlements was $4.2 million. For the three months ended September 30, 2015 and 2014, amortization of financing costs was $0.5 million and $2.0 million, respectively. During the nine months ended September 30, 2015 and 2014, amortization of financing costs was $1.3 million and $2.9 million. In connection with our debt repayments during the three months ended September 30, 2014, we expensed $1.5 million of deferred financing costs. For more information on our long-term debt and interest rates on that debt, see Note 10, Debt, of the Notes to Consolidated Financial Statements in "Part II, Item 8. Financial Statements and Supplementary Data" of our 2014 Annual Report on Form 10-K. At September 30, 2015, we had $1,647.2 million of fixed-rate senior notes and $678.6 million of variable-rate term loans outstanding. At September 30, 2015, the fair value of our fixed-rate debt was estimated to be $1,711.9 million. The difference between the book value and fair value is due to the difference between the period-end market interest rate and the stated rate of our fixed-rate debt. We estimated the fair value of our fixed-rate debt using quoted market prices (Level 2 inputs) within the fair value hierarchy, which is further defined in Note 2, Summary of Significant Accounting Policies, of the Notes to Consolidated Financial Statements in "Part II, Item 8. Financial Statements and Supplementary Data" of our 2014 Annual Report on Form 10-K. The fair value of our variable-rate term debt approximates the carrying amount as our cost of borrowing is variable and approximates current market rates.

Debt

During the nine months ended September 30, 2015, we made principal payments of $25.0 million on our five-year term loan due October 2018, and $4.9 million on our seven-year term loan, due October 2020.

On September 5, 2014, we issued $400.0 million of 3.65% fixed-rate senior notes due September 15, 2024, through a registered public offering. We used the proceeds of this offering and other cash from operations to repay $589.9 million of debt during the nine months ended September 30, 2014.

For the nine months ended September 30, 2015 and 2014, cash payments for interest were $58.6 million and $50.0 million, respectively.

Included in interest expense, net, are amortization of treasury lock settlements and amortization of financing costs. For both the three months ended September 30, 2015 and 2014, amortization of treasury lock settlements was $1.4 million, and for both the nine months ended September 30, 2015 and 2014, amortization of treasury lock settlements was $4.2 million. For the three months ended September 30, 2015 and 2014, amortization of financing costs was $0.5 million and $2.0 million, respectively. During the nine months ended September 30, 2015 and 2014, amortization of financing costs was $1.3 million and $2.9 million. In connection with our debt repayments during the three months ended September 30, 2014, we expensed $1.5 million of deferred financing costs.

For more information on our long-term debt and interest rates on that debt, see Note 10, Debt, of the Notes to Consolidated Financial Statements in "Part II, Item 8. Financial Statements and Supplementary Data" of our 2014 Annual Report on Form 10-K.

At September 30, 2015, we had $1,647.2 million of fixed-rate senior notes and $678.6 million of variable-rate term loans outstanding. At September 30, 2015, the fair value of our fixed-rate debt was estimated to be $1,711.9 million. The difference between the book value and fair value is due to the difference between the period-end market interest rate and the stated rate of our fixed-rate debt. We estimated the fair value of our fixed-rate debt using quoted market prices (Level 2 inputs) within the fair value hierarchy, which is further defined in Note 2, Summary of Significant Accounting Policies, of the Notes to Consolidated Financial Statements in "Part II, Item 8. Financial Statements and Supplementary Data" of our 2014 Annual Report on Form 10-K. The fair value of our variable-rate term debt approximates the carrying amount as our cost of borrowing is variable and approximates current market rates.