Derivative Financial Instruments - Master Netting Arrangements (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	$ 379,376	$ 163,374
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Assets Presented in the Statement of Financial Position	379,376	163,369
Gross Assets Subject To Master Netting Arrangement Not Offset	(349,594)	(150,979)
Cash Collateral Received Subject to Master Netting Arrangements	(3,219)	(1,900)
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	26,563	10,490
Gross Amounts of Recognized Liabilities	55,195	30,742
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Liabilities Presented in the Statement of Financial Position	55,195	30,737
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(36,620)	(15,202)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	18,575	15,535
Derivative
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	63,317	37,983
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Assets Presented in the Statement of Financial Position	63,317	37,978
Gross Assets Subject To Master Netting Arrangement Not Offset	(33,535)	(25,588)
Cash Collateral Received Subject to Master Netting Arrangements	(3,219)	(1,900)
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	26,563	10,490
Gross Amounts of Recognized Liabilities	55,195	30,742
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Liabilities Presented in the Statement of Financial Position	55,195	30,737
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(36,620)	(15,202)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	18,575	15,535
Derivative | Interest rate swaps
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	1,918	2,768
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	1,918	2,768
Gross Assets Subject To Master Netting Arrangement Not Offset	(1,918)	(2,768)
Cash Collateral Received Subject to Master Netting Arrangements	0	0
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	0	0
Derivative | Foreign exchange forwards
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	51,231	30,531
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	51,231	30,531
Gross Assets Subject To Master Netting Arrangement Not Offset	(22,301)	(18,141)
Cash Collateral Received Subject to Master Netting Arrangements	(3,219)	(1,900)
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	25,711	10,490
Gross Amounts of Recognized Liabilities	43,926	25,647
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	43,926	25,647
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(25,658)	(10,818)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	18,268	14,829
Derivative | Client foreign currency options
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	1,614	711
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Assets Presented in the Statement of Financial Position	1,614	706
Gross Assets Subject To Master Netting Arrangement Not Offset	(786)	(706)
Cash Collateral Received Subject to Master Netting Arrangements	0	0
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	828	0
Gross Amounts of Recognized Liabilities	1,614	711
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Liabilities Presented in the Statement of Financial Position	1,614	706
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(1,307)	0
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	307	706
Derivative | Client interest rate derivatives
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	8,554	3,973
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	8,554	3,973
Gross Assets Subject To Master Netting Arrangement Not Offset	(8,530)	(3,973)
Cash Collateral Received Subject to Master Netting Arrangements	0	0
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	24	0
Gross Amounts of Recognized Liabilities	9,655	4,384
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	9,655	4,384
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(9,655)	(4,384)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	0	0
Reverse Repurchase Securities Borrowing And Similar Arrangements
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	316,059	125,391
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	316,059	125,391
Gross Assets Subject To Master Netting Arrangement Not Offset	(316,059)	(125,391)
Cash Collateral Received Subject to Master Netting Arrangements	0	0
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	0	0
Gross Amounts of Recognized Liabilities	0	0
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	0	0
Gross Liabilities Subject To Master Netting Arrangement Not Offset	0	0
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	$ 0	$ 0