CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Shares of Common Stock (no par value)	Additional Paid in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2015	$ 289,938		$ 32,776	$ 256,747	$ 415
Balance (in shares) at Dec. 31, 2015		48,475
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(895)			(895)
Other comprehensive gain (loss), net of tax	6,373				6,373
Dividends declared	(12,228)			(12,228)
Dividends reinvested in common stock	524		524
Dividends reinvested in common stock (in shares)		19
Stock based compensation	3,506		3,506
Common stock issued through exercise of incentive stock options	3,359		3,359
Common stock issued through exercise of incentive stock options (in shares)		371
Common stock issued for share awards (in shares)		190
Common stock issued	14		14
Common stock issued (in shares)		2
Common stock issued to acquire non-controlling interest in nTelos	10,400		10,400
Common stock issued to acquire a non-controlling interests of nTelos (in shares)		76
Shares retired for settlement of employee taxes upon issuance of vested equity awards	(5,097)		(5,097)
Shares retired for settlement of employee taxes upon issuance of vested equity awards (in shares)		(198)
Balance at Dec. 31, 2016	295,894		45,482	243,624	6,788
Balance (in shares) at Dec. 31, 2016		48,935
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	66,390			66,390
Other comprehensive gain (loss), net of tax	1,442				1,442
Dividends declared	(12,809)			(12,809)
Dividends reinvested in common stock	552		552
Dividends reinvested in common stock (in shares)		15
Stock based compensation	4,184		4,184
Stock based compensation (in shares)		154
Common stock issued through exercise of incentive stock options	2,394		2,394
Common stock issued through exercise of incentive stock options (in shares)		363
Common stock issued	21		21
Common stock issued (in shares)		1
Common stock issued to acquire a non-controlling interests of nTelos (in shares)		76
Shares retired for settlement of employee taxes upon issuance of vested equity awards	(7,846)		(7,846)
Shares retired for settlement of employee taxes upon issuance of vested equity awards (in shares)		(216)
Balance at Dec. 31, 2017	$ 350,222		44,787	297,205	8,230
Balance (in shares) at Dec. 31, 2017	49,328	49,328
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 46,595			46,595
Other comprehensive gain (loss), net of tax	50				50
Dividends declared	(13,386)			(13,386)
Dividends reinvested in common stock	520		520
Dividends reinvested in common stock (in shares)		11
Stock based compensation	5,367		5,367
Stock based compensation (in shares)		206
Common stock issued through exercise of incentive stock options	787		787
Common stock issued through exercise of incentive stock options (in shares)		113
Common stock issued	26		26
Common stock issued (in shares)		1
Common stock issued to acquire a non-controlling interests of nTelos (in shares)		76
Shares retired for settlement of employee taxes upon issuance of vested equity awards	(4,031)		(4,031)
Shares retired for settlement of employee taxes upon issuance of vested equity awards (in shares)		(105)
Balance at Dec. 31, 2018	$ 442,247		$ 47,456	$ 386,511	$ 8,280
Balance (in shares) at Dec. 31, 2018	49,630	49,630