Fair Values of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2014

Fair Value Disclosures [Abstract]

Carrying Amounts and Fair Values of Financial Instruments

The carrying amounts, including fair value adjustments previously recognized in acquisition purchase accounting and a fair value adjustment related to the Company’s interest rate swap fair value hedge (which is classified as Level 2 in the fair value hierarchy), and fair values of the financial instruments are as follows:

	Carrying		At Fair Value as of December 31, 2014
	Amount		Level 1		Level 2		Level 3		Total
Preferred stock with mandatory redemption      requirements	$	17,151	$               —		$               —		$	22,167	$	22,167
Long-term debt (excluding capital lease      obligations)		5,491,341		2,874,622		1,474,708		2,055,058		6,404,388

	Carrying		At Fair Value as of December 31, 2013
	Amount		Level 1		Level 2		Level 3		Total
Preferred stock with mandatory redemption      requirements	$	18,827	$               —		$               —		$	22,795	$	22,795
Long-term debt (excluding capital lease      obligations)		5,224,492		2,263,355		1,462,404		2,057,506		5,783,265

Fair Value Measurements of Assets and Liabilities on Recurring Basis

Recurring Fair Value Measurements

The following table presents assets and liabilities measured and recorded at fair value on a recurring basis and their level within the fair value hierarchy as of December 31, 2014 and 2013, respectively:

Recurring Fair Value Measures	At Fair Value as of December 31, 2014
	Level 1		Level 2		Level 3	Total
Assets:
Restricted funds	$	45,182	$                —		$                —	$	45,182
Rabbi trust investments	—			11,751	—		11,751
Deposits		4,158	—		—		4,158
Mark-to-market derivative asset	—			3,636	—		3,636
Total assets		49,340		15,387	—		64,727
Liabilities:
Deferred compensation obligation	—			11,765	—		11,765
Mark-to-market derivative liability	—			1,012	—		1,012
Total liabilities	—			12,777	—		12,777
Total net assets	$	49,340	$	2,610	$                —	$	51,950

Recurring Fair Value Measures	At Fair Value as of December 31, 2013
	Level 1		Level 2			Level 3	Total
Assets:
Restricted funds	$	29,259	$                —			$                —	$	29,259
Rabbi trust investments	—			444		—		444
Deposits		1,901	—			—		1,901
Mark-to-market derivative asset	—			4,776		—		4,776
Total assets		31,160		5,220		—		36,380
Liabilities:
Deferred compensation obligation	—			11,928		—		11,928
Mark-to-market derivative liability	—			1,276		—		1,276
Total liabilities	—			13,204		—		13,204
Total net assets (liabilities)	$	31,160	$	(7,984	)	$                —	$	23,176