Acquisitions Acquisitions (Details 1) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Combinations [Abstract]
Business Combination, Severance and Employee-related	[1]									$ 10,550	$ 57,868	$ 21,497
Business Combination, System Conversion and Integration										4,246	1,868	3,829
Business Combinations, Asset Writedowns Lease Terminations and other facilities-related										125	6,353	3,212
Business Combinations, Segment or Division reorganization										0	10,073	0
Business Combinations, Banking Fees										1,050	16,117	5,309
Business Combinations, Other Expenses										5,276	8,737	6,965
Acquisition, integration and reorganization costs		$ 107,849	$ 84,871	$ 86,716	$ 82,024	$ 81,986	$ 84,903	$ 82,461	$ 49,825	$ 21,247	101,016	40,812
Expense incurred due to awarded shares of restricted common stock vested due to the triggering of the change of control provision contained within the 2003 Plan											$ 26,100	$ 12,400

[1] Amount includes $26.1 million in 2014 and $12.4 million in 2013 for accelerated vesting of restricted stock awards.