Acquisition Activity - Assets Acquired and Liabilities Assumed (Details) - USD ($)	Mar. 31, 2018	Mar. 23, 2018	Jan. 12, 2018	Jul. 31, 2017
Assets
Non-compete agreement			$ 155,900
Gibraltar Private Bank & Trust Company
Assets
Cash and cash equivalents		$ 102,570,000
Investment securities		19,169,000
Equity securities		27,519,000
Loans	$ 1,500,000,000	1,465,319,000
Core deposit intangible assets		18,529,000
Deferred tax asset, net		689,000
Other assets		14,382,000
Total assets acquired		1,648,177,000
Liabilities
Deposit liabilities		1,064,803,000
Long-term borrowings		405,107,000
Other liabilities		6,131,000
Total liabilities assumed		$ 1,476,041,000
Solomon Parks Title & Escrow
Assets
Premise and equipment, net			42,000
Non-compete agreement			156,000
Title Plant investment			15,000
Total assets acquired			213,000
Liabilities
Contingent consideration			343,000
Total liabilities assumed			$ 343,000
Sabadell United
Assets
Cash and cash equivalents				$ 318,834,000
Investment securities				964,123,000
Loans				4,025,946,000
Core deposit intangible assets				66,600,000
Deferred tax asset, net				33,469,000
Other assets				89,745,000
Total assets acquired				5,498,717,000
Liabilities
Deposit liabilities				4,382,780,000
Short-term borrowings				520,539,000
Other liabilities				38,599,000
Total liabilities assumed				$ 4,941,918,000