Commitments and Contingent Liabilities (Tables)

12 Months Ended

Dec. 31, 2013

Commitments and Contingencies Disclosure [Abstract]

Schedule of Guarantor Obligations [Table Text Block]

	Maximum Potential Obligation
Commitment Period	2013		2012
2026	$	500.0	$	—
2033	1,350.0		—
2035	—		560.0
2036	1,250.0		—

Credit Facilities [Table Text Block]

The following table provides additional information on the Company’s credit facilities as of December 31, 2013 and 2012 (dollars in millions):

			Amount Utilized(1) December 31,
Facility Capacity		Maturity Date	2013		2012		Basis of Fees
$	850.0	December 2015	$	67.6	$	402.9	Senior unsecured long-term debt rating
200.0		September 2019	200.0		200.0		Fixed
120.0		May 2016	85.1		100.0		Fixed
270.0		November 2017	270.0		—		Fixed
100.0		June 2017	89.4		—		Fixed
58.4		November 2014	58.4		—		Fixed
132.5		March 2019	132.5		—		Fixed

(1) Represents issued but undrawn letters of credit. There was no cash borrowed for the periods presented.

Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]

Future minimum office space annual rentals under non-cancelable operating leases along with associated sublease income at December 31, 2013 are as follows (dollars in thousands):

	Operating Leases		Sublease Income
2014	$	16,905	$	827
2015	10,862		827
2016	8,434		776
2017	5,638		160
2018	4,466		—
Thereafter	15,489		—