Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2016

Fair Value Disclosures [Abstract]

Carrying Amounts and Fair Values of Company's Amended and Restated Senior Credit Facilities, Derivative Instruments and Contingent Consideration Liabilities

The carrying amounts and fair values of the Company’s Amended and Restated Senior Credit Facility, 6.125% Senior Notes, 5.125% Senior Notes, 5.625% Senior Notes, 6.500% Senior Notes, 9.0% and 9.5% Revenue Bonds, derivative instruments and contingent consideration liabilities as of June 30, 2016 and December 31, 2015 were as follows (in thousands):

	Carrying Amount				Fair Value
	June 30, 2016		December 31, 2015		June 30, 2016		December 31, 2015
Amended and Restated Senior Credit Facility	$	2,164,959	$	1,135,861	$	2,164,959	$	1,135,861
6.125% Senior Notes due 2021	$	147,324	$	147,082	$	151,375	$	149,288
5.125% Senior Notes due 2022	$	295,090	$	294,749	$	286,237	$	275,590
5.625% Senior Notes due 2023	$	639,990	$	639,431	$	627,190	$	604,262
6.500% Senior Notes due 2024	$	381,173	$	—	$	386,891	$	—
9.0% and 9.5% Revenue Bonds	$	23,407	$	23,621	$	23,407	$	23,621
Derivative instruments	$	40,459	$	—	$	40,459	$	—
Contingent consideration liabilities	$	667	$	667	$	667	$	667