Loans (Summary of Recorded Investment of Consumer Loans by Risk Rating Categories) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	$ 12,715,789	$ 7,271,147
Nonperforming [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	61,651	83,880
Consumer loan portfolio [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	5,282,342	3,021,030
Consumer loan portfolio [Member] | Residential mortgage [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	3,046,959	1,429,636
Consumer loan portfolio [Member] | Consumer installment [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,335,707	877,457
Consumer loan portfolio [Member] | Home equity [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	899,676	713,937
Originated Portfolio [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	3,135,207	2,677,213
Originated Portfolio [Member] | Residential mortgage [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,371,004	1,216,975
Originated Portfolio [Member] | Consumer installment [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,172,137	869,426
Originated Portfolio [Member] | Home equity [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	592,066	590,812
Originated Portfolio [Member] | Performing [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	3,124,952	2,664,486
Originated Portfolio [Member] | Performing [Member] | Residential mortgage [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,363,819	1,207,945
Originated Portfolio [Member] | Performing [Member] | Consumer installment [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,171,759	868,975
Originated Portfolio [Member] | Performing [Member] | Home equity [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	589,374	587,566
Originated Portfolio [Member] | Nonperforming [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	10,255	12,727
Originated Portfolio [Member] | Nonperforming [Member] | Residential mortgage [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	7,185	9,030
Originated Portfolio [Member] | Nonperforming [Member] | Consumer installment [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	378	451
Originated Portfolio [Member] | Nonperforming [Member] | Home equity [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	2,692	3,246
Acquired Portfolio [Member] | Performing [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	2,147,135	343,817
Acquired Portfolio [Member] | Performing [Member] | Residential mortgage [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,675,955	212,661
Acquired Portfolio [Member] | Performing [Member] | Consumer installment [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	163,570	8,031
Acquired Portfolio [Member] | Performing [Member] | Home equity [Member]
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	$ 307,610	$ 123,125