Goodwill and Intangible Assets (Schedule of Goodwill and Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Goodwill and Intangible Assets [Line Items]
Goodwill, Acquired During Period	$ 0	$ 228,398	$ 0	$ 228,398
Indefinite-Lived Intangible Assets (Excluding Goodwill)	919	913	919	913
Intangible Assets, Net (Excluding Goodwill)	22,792	29,170	22,792	29,170		25,852
Goodwill and Intangible Assets [Roll Forward]
Total goodwill, beginning of period			343,952	115,554
Total goodwill, end of period	343,952	343,952	343,952	343,952
CDI current period amortization	(1,480)	(1,693)	(3,060)	(2,722)
Total goodwill and intangible assets, end of period	366,744	373,122	366,744	373,122
Core Deposits [Member]
Goodwill and Intangible Assets [Line Items]
Finite Lived Intangible Assets Acquired During the Period	0	15,257	0	15,257
Estimated life of CDI, in years			10 years
Goodwill and Intangible Assets [Roll Forward]
Gross core deposit intangible balance, beginning of period					47,698	47,698	32,441	32,441
Accumulated amortization at beginning of period					(24,344)	(22,765)	(17,748)	(16,720)
Core deposit intangible, net, beginning of period	23,354	14,693	24,933	15,721
CDI current period amortization	(1,481)	(1,693)	(3,060)	(2,721)
Total core deposit intangible, end of period	$ 21,873	$ 28,257	$ 21,873	$ 28,257