UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), Net of Tax [Member]
Beginning balance at Dec. 31, 2014	$ 258,346	$ 29,712	$ 227,512	$ 1,122
Beginning balance (in shares) at Dec. 31, 2014		48,265
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	40,864		40,864
Other comprehensive loss, net of tax	(707)			(707)
Dividends declared ($0.24 per share)	(11,629)		(11,629)
Dividends reinvested in common stock	544	$ 544
Dividends reinvested in common stock (in shares)		22
Stock based compensation	2,719	$ 2,719
Stock options exercised	996	$ 996
Stock options exercised (in shares)		87
Common stock issued for share awards	0
Common stock issued for share awards (in shares)		212
Common stock issued	11	$ 11
Common stock issued (in shares)		1
Common stock repurchased	(1,885)	$ (1,885)
Common stock repurchased (in shares)		(111)
Net excess tax benefit from stock options exercised	679	$ 679
Ending balance at Dec. 31, 2015	289,938	$ 32,776	256,747	415
Ending balance (in shares) at Dec. 31, 2015		48,475
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(711)		(711)
Other comprehensive loss, net of tax	(2,573)			(2,573)
Stock based compensation	2,980	$ 2,980
Stock options exercised	3,362	$ 3,362
Stock options exercised (in shares)		371
Common stock issued for share awards (in shares)		190
Common stock issued	6	$ 6
Common stock issued (in shares)		1
Common stock issued to acquire non-controlling interests of nTelos	10,400	$ 10,400
Common stock issued to acquire non-controlling interests of nTelos (in shares)		76
Common stock repurchased	(5,097)	$ (5,097)
Common stock repurchased (in shares)		(198)
Ending balance at Sep. 30, 2016	$ 298,306	$ 44,427	$ 256,037	$ (2,158)
Ending balance (in shares) at Sep. 30, 2016		48,915