Derivative Financial Instruments - Master Netting Arrangements (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	$ 222,864	$ 163,374
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Assets Presented in the Statement of Financial Position	222,864	163,369
Gross Assets Subject To Master Netting Arrangement Not Offset	(194,385)	(150,979)
Cash Collateral Received Subject to Master Netting Arrangements	(2,421)	(1,900)
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	26,058	10,490
Gross Amounts of Recognized Liabilities	48,838	30,742
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Liabilities Presented in the Statement of Financial Position	48,838	30,737
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(28,924)	(15,202)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	19,914	15,535
Derivative
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	59,145	37,983
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Assets Presented in the Statement of Financial Position	59,145	37,978
Gross Assets Subject To Master Netting Arrangement Not Offset	(30,666)	(25,588)
Cash Collateral Received Subject to Master Netting Arrangements	(2,421)	(1,900)
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	26,058	10,490
Gross Amounts of Recognized Liabilities	48,838	30,742
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Liabilities Presented in the Statement of Financial Position	48,838	30,737
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(28,924)	(15,202)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	19,914	15,535
Derivative | Interest rate swaps
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	1,324	2,768
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	1,324	2,768
Gross Assets Subject To Master Netting Arrangement Not Offset	(1,324)	(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	46,312	30,531
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	46,312	30,531
Gross Assets Subject To Master Netting Arrangement Not Offset	(19,377)	(18,141)
Cash Collateral Received Subject to Master Netting Arrangements	(2,421)	(1,900)
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	24,514	10,490
Gross Amounts of Recognized Liabilities	36,764	25,647
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	36,764	25,647
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(17,675)	(10,818)
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	19,089	14,829
Derivative | Client foreign currency options
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	2,750	711
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Assets Presented in the Statement of Financial Position	2,750	706
Gross Assets Subject To Master Netting Arrangement Not Offset	(1,246)	(706)
Cash Collateral Received Subject to Master Netting Arrangements	0	0
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	1,504	0
Gross Amounts of Recognized Liabilities	2,750	711
Gross Amounts offset in the Statement of Financial Position	0	(5)
Net Amounts of Liabilities Presented in the Statement of Financial Position	2,750	706
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(1,925)	0
Cash Collateral Pledged Subject to Master Netting Arrangements	0	0
Net Liabilities After Deducting Amounts Subject to Master Netting Arrangements	825	706
Derivative | Client interest rate derivatives
Assets and Liabilities Subject to Master Netting Arrangements [Line Items]
Gross Amounts of Recognized Assets	8,759	3,973
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	8,759	3,973
Gross Assets Subject To Master Netting Arrangement Not Offset	(8,719)	(3,973)
Cash Collateral Received Subject to Master Netting Arrangements	0	0
Net Assets After Deducting Amounts Subject to Master Netting Arrangements	40	0
Gross Amounts of Recognized Liabilities	9,324	4,384
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	9,324	4,384
Gross Liabilities Subject To Master Netting Arrangement Not Offset	(9,324)	(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	163,719	125,391
Gross Amounts offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	163,719	125,391
Gross Assets Subject To Master Netting Arrangement Not Offset	(163,719)	(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