Restructuring Charges (Details) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	$ 16,923,000		$ 7,981,000	$ 0
2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Number of employees impacted	250
Total Anticipated Charges	13,000,000
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring liability at the beginning of period	0
Restructuring charges	13,421,000	[1]
Non-cash items	(137,000)
Cash paid	(5,990,000)
Foreign exchange rate changes	160,000
Restructuring liability at the end of period	7,454,000
2013 Restructuring Plan | North America
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	660,000	[1]
2013 Restructuring Plan | International
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	12,116,000	[1]
2013 Restructuring Plan | Other
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	64,000	[1]
2013 Restructuring Plan | Corporate
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	581,000	[1]
2012 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred to date	11,483,000	[2]
Total estimated non-cash restructuring charges	1,000,000
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring liability at the beginning of period	5,088,000		0
Restructuring charges	3,502,000		7,981,000
Non-cash items	510,000		(675,000)
Cash paid	(6,272,000)		(2,218,000)
Foreign exchange rate changes	(58,000)
Restructuring liability at the end of period	2,770,000		5,088,000
2012 Restructuring Plan | North America
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred to date	1,705,000	[2]
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	241,000
2012 Restructuring Plan | International
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred to date	7,080,000	[2]
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	1,306,000
2012 Restructuring Plan | Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred to date	2,698,000	[2],[3]
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring charges	1,955,000	[3]
2012 Restructuring Plan | Employee Severance and Termination
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring liability at the beginning of period	3,556,000		0
Restructuring charges	370,000		6,517,000
Non-cash items	0		(743,000)
Cash paid	(3,851,000)		(2,218,000)
Foreign exchange rate changes	(75,000)
Restructuring liability at the end of period	0		3,556,000
2012 Restructuring Plan | Employee Severance and Termination | International
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred to date	7,000,000
2012 Restructuring Plan | Office Closures
Restructuring Cost and Reserve [Line Items]
Number of offices closed	17
Changes in restructuring liabilities, recorded in other accrued expenses
Restructuring liability at the beginning of period	1,532,000		0
Restructuring charges	3,132,000		1,464,000
Non-cash items	510,000		68,000
Cash paid	(2,421,000)		0
Foreign exchange rate changes	17,000
Restructuring liability at the end of period	2,770,000		1,532,000
2012 Restructuring Plan | Office Closures | International
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred to date	$ 4,000,000

[1] As a majority of the actions have been completed through December 31, 2013, the total charges to date approximate the total anticipated charges by segment.

[2] Our restructuring charges, particularly lease-related office closure costs, are subject to estimate. If we are unable to find tenants for vacated offices or sub-lease terms are different from our estimates, our actual restructuring charges will differ from our current estimates.

[3] 2012 corporate restructuring charges consist of share-based compensation expenses associated with severance for employees in our International division. Share-based compensation is not charged to operating divisions, but rather is recorded as part of our corporate expenses. 2013 corporate restructuring charges include costs for administrative facility consolidation. (1) As a majority of the actions have been completed through December 31, 2013, the total charges to date approximate the total anticipated charges by segment.