Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands		Total	Common Stock	Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Loss	Retained Earnings	Noncontrolling Interest
Beginning Balance (in shares) at Dec. 31, 2015			20,931,416
Beginning Balance at Dec. 31, 2015		$ 365,711	$ 20,931	$ 228,814	$ (58,144)	$ (412)	$ 174,522	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		36,036					36,036
Tax provision-to-return adjustment related to excess tax benefit on stock-based compensation		197		197
Dividends declared		(13,989)					(13,989)
Change in other comprehensive loss		(1,997)				(1,997)
Stock based compensation		1,713		1,713
Retirement of treasury stock (in shares)			(4,320)
Retirement of treasury stock		0	$ (4)	(39)	43
Net purchase of treasury stock from stock awards for statutory tax withholdings		(7,971)			(7,971)
Net purchase of treasury stock from stock award and deferred compensation plans		$ (878)			(878)
Share-based awards and options exercises (in shares)		105,830	183,872
Share-based awards and options exercises		$ 2,305	$ 184	2,121
Ending Balance (in shares) at Dec. 31, 2016			21,110,968
Ending Balance at Dec. 31, 2016		381,127	$ 21,111	232,806	(66,950)	(2,409)	196,569	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		23,016					23,016
Dividends declared		(14,818)					(14,818)
Change in other comprehensive loss		(1,223)				(1,223)	0
Stock based compensation		2,068		2,068
Retirement of treasury stock (in shares)			(2,628)
Retirement of treasury stock		0	$ (3)	(23)	26
Net purchase of treasury stock from stock awards for statutory tax withholdings		(1,140)			(1,140)
Net purchase of treasury stock from stock award and deferred compensation plans		$ (115)			(115)
Share-based awards and options exercises (in shares)		69,527	152,955
Share-based awards and options exercises		$ 1,611	$ 153	1,458
Reclassification of Tax Effects From AOCI		0				(782)	782
Form S-4 stock issuance costs		(233)		(233)
Stock warrants assumed in acquisitions		1,854		1,854
Noncontrolling interest assumed in acquisitions		(683)						(683)
Shares issued in acquisitions (in shares)			3,098,754
Shares issued in acquisitions		$ 136,655	$ 3,099	133,556
Ending Balance (in shares) at Dec. 31, 2017		24,360,049	24,360,049
Ending Balance at Dec. 31, 2017		$ 528,119	$ 24,360	371,486	(68,179)	(4,414)	205,549	(683)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		63,792					63,792	0
Dividends declared		(19,209)					(19,209)
Change in other comprehensive loss		(3,099)				(3,099)
Stock based compensation		2,750		2,750
Retirement of treasury stock (in shares)			2,253
Retirement of treasury stock		0	$ (2)	(20)	22
Net purchase of treasury stock from stock awards for statutory tax withholdings		$ (1,639)			(1,639)
Share-based awards and options exercises (in shares)		64,645	184,990
Share-based awards and options exercises		$ 1,566	$ 184	1,382
Reclassification of Tax Effects From AOCI							782
Shares issued in acquisitions (in shares)	[1]		2,562
Shares issued in acquisitions	[1]	113	$ 3	110
Net income attributable to noncontrolling interest		0					0	0
Goodwill measurement period adjustment effect on noncontrolling interest		0		2				(2)
Net treasury stock activity for deferred compensation trusts		2		153	(151)
Purchase of treasury stock through publicly announced plans		(5,936)			(5,936)
Repurchase of warrants from U.S. Treasury		$ (1,755)		(1,853)			98
Ending Balance (in shares) at Dec. 31, 2018		24,545,348	24,545,348
Ending Balance at Dec. 31, 2018		$ 564,704	$ 24,545	$ 374,010	$ (75,883)	$ (7,513)	$ 250,230	$ (685)

[1] Shares relating to the RBPI Merger (defined in Note 3, “Business Combinations,” below) recorded in April 2018.