Operating Segments (Financial Results By Operating Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Sep. 30, 2015	Mar. 31, 2015	Dec. 31, 2015
Financial results by operating segment
Net interest income (loss)	$ 19,840	$ 19,840	$ 15,610
Provision (credit) for loan losses	4,375	4,375	(1,887)
Noninterest income	3,415	3,415	2,840
Noninterest expenses	15,996	15,996	13,082
Income (loss) before taxes	2,884	2,884	7,255
Taxes on income (loss)	1,015	1,015	2,720
Net income (loss)	1,869	$ 1,869	4,535
Externally generated revenue from investing activities	900		400
Internally generated loss from fund management	800		1,000
Total loans at period end	1,781,884		1,438,245
Total assets at period end	2,360,819		2,003,079
Total goodwill at period end	13,467			$ 13,467
Total deposits at period end	1,895,248		1,616,454
Oklahoma Banking [Member]
Financial results by operating segment
Net interest income (loss)	12,938		9,735
Provision (credit) for loan losses	260		(1,233)
Noninterest income	2,195		2,039
Noninterest expenses	9,960		7,345
Income (loss) before taxes	4,913		5,662
Taxes on income (loss)	1,729		2,123
Net income (loss)	3,184		3,539
Total loans at period end	1,060,483		814,949
Total assets at period end	1,105,545		828,576
Total deposits at period end	1,359,179		1,132,015
Texas Banking [Member]
Financial results by operating segment
Net interest income (loss)	5,566		5,220
Provision (credit) for loan losses	1,915		(250)
Noninterest income	302		309
Noninterest expenses	3,731		3,435
Income (loss) before taxes	222		2,344
Taxes on income (loss)	78		879
Net income (loss)	144		1,465
Total loans at period end	560,421		478,005
Total assets at period end	556,405		476,075
Total deposits at period end	195,593		254,665
Kansas Banking [Member]
Financial results by operating segment
Net interest income (loss)	1,828		1,463
Provision (credit) for loan losses	2,199		(403)
Noninterest income	318		302
Noninterest expenses	1,417		1,609
Income (loss) before taxes	(1,470)		559
Taxes on income (loss)	(517)		209
Net income (loss)	(953)		350
Total loans at period end	160,980		145,291
Total assets at period end	160,031		145,552
Total deposits at period end	130,283		124,094
Other Operations [Member]
Financial results by operating segment
Net interest income (loss)	(492)		(808)
Provision (credit) for loan losses	1		(1)
Noninterest income	600		190
Noninterest expenses	888		693
Income (loss) before taxes	(781)		(1,310)
Taxes on income (loss)	(275)		(491)
Net income (loss)	(506)		(819)
Total assets at period end	538,838		552,876
Total deposits at period end	$ 210,193		$ 105,680