Acquisitions - Assets Acquired and Liabilities Assumed - Schedule (Details) - USD ($) $ in Thousands		12 Months Ended
	Jul. 01, 2018	Jun. 30, 2019	Dec. 31, 2018
LIABILITIES ASSUMED
Goodwill recognized		$ 808,322	$ 808,726
Grandpoint Capital, Inc.
ASSETS ACQUIRED
Cash and cash equivalents	$ 147,551	147,551
Investment securities	395,905	392,858
Loans, gross	2,404,042	2,352,717
Allowance for loan losses	(18,665)	0
Fixed assets	6,015	9,122
Core deposit intangible	5,093	71,943
Deferred tax assets	14,185	5,028
Other assets	97,441	97,005
Total assets acquired	3,051,567	3,076,224
LIABILITIES ASSUMED
Deposits	2,506,663	2,506,929
Borrowings	255,155	254,923
Other Liabilities	23,687	24,859
Total liabilities assumed	2,785,505	2,786,711
Excess of assets acquired over liabilities assumed	266,062	289,513
Consideration paid	602,152
Goodwill recognized	$ 312,600	312,639
Fair Value Adjustments
Cash and cash equivalents		0
Investment securities		(3,047)
Loans, gross		(51,325)
Allowance for loan losses		18,665
Fixed assets		3,107
Core deposit intangible		66,850
Deferred tax assets		(9,157)
Other assets		(436)
Total assets acquired		24,657
Deposits		266
Borrowings		(232)
Other Liabilities		1,172
Total liabilities assumed		1,206
Excess of assets acquired over liabilities assumed		$ 23,451