CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income		$ 27,303	$ 28,002	$ 14,176	$ 55,305	$ 23,697
Other comprehensive income, net of tax:
Unrealized holding (loss)/gain on securities arising during the period, net of income taxes	[1]	(3,122)	(9,343)	6,336	(12,465)	7,349
Reclassification adjustment for net (gains) losses on sale of securities included in net income, net of income taxes	[2]	(240)	(5)	(1,368)	(245)	(1,368)
Other comprehensive (loss) income, net of tax		(3,362)	(9,348)	4,968	(12,710)	5,981
Comprehensive income, net of tax		$ 23,941	$ 18,654	$ 19,144	$ 42,595	$ 29,678

[1] Income tax (benefit) expense on the unrealized (loss)/gain on securities was $(1.3) million for the three months ended June 30, 2018, $(3.9) million for the three months ended March 31, 2018, $4.3 million for the three months ended June 30, 2017, $(5.2) million for the six months ended June 30, 2018 and $5.0 million for the six months ended June 30, 2017.

[2] Income tax expense (benefit) on the reclassification adjustment for net (gains) losses on sale of securities included in net income was $90,000 for the three months ended June 30, 2018, $1,000 for the three months ended March 31, 2018, $725,000 for the three months ended June 30, 2017, $91,000 for the six months ended June 30, 2018 and $725,000 for the six months ended June 30, 2017.