CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Operating revenues	$ 535,288	$ 342,485	$ 326,946
Operating expenses
Cost of goods and services, exclusive of depreciation and amortization shown separately below	193,520	121,330	129,743
Selling, general and administrative, exclusive of depreciation and amortization shown below	133,325	72,821	69,370
Integration and acquisition expenses	42,232	3,546	0
Depreciation and amortization	143,685	70,702	65,890
Total operating expenses	512,762	268,399	265,003
Operating income	22,526	74,086	61,943
Other income (expense)
Interest expense	(25,102)	(7,355)	(8,148)
Gain on investments, net	271	105	208
Non-operating income, net	4,250	1,754	2,031
Income before income taxes	1,945	68,590	56,034
Income tax expense	2,840	27,726	22,151
Net income (loss)	(895)	40,864	33,883
Other comprehensive income:
Unrealized gain (loss) on interest rate hedge, net of tax	6,373	(707)	(1,472)
Comprehensive income	$ 5,478	$ 40,157	$ 32,411
Earnings (loss) per share:
Basic (in dollars per share)	$ (0.02)	$ 0.84	$ 0.70
Diluted (in dollars per share)	$ (0.02)	$ 0.83	$ 0.70
Weighted average shares outstanding, basic (in shares)	48,807	48,388	48,198
Weighted average shares outstanding, diluted (in shares)	48,807	49,024	48,720