Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Investments, All Other Investments [Abstract]

Summary of Carrying Amounts and Estimated Fair Values of Other Financial Instruments

The following table summarizes the carrying amounts and estimated fair values of our other financial instruments at March 31, 2018:

	Carrying Amount		Fair Value
	(Dollars in thousands)
Assets:
Cash and cash equivalents	$	174,540	$	174,540
Liabilities:
Bank debt	$	1,268,497	$	1,268,497
5% Senior Notes	280,000		280,162
5½% Senior Notes	300,000		306,195
4¾% Senior Notes	300,000		291,585
3¼% Senior Notes	801,060		817,105
Derivative instruments (accrued and other liabilities)	626		626