Additional Details Related to Certain Balance Sheet Captions (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
Other current assets
Prepaid taxes	$ 108,200,000	$ 40,000,000
Prepaid expenses	46,100,000	48,100,000
Other	42,900,000	26,300,000
Total other current assets	197,200,000	114,400,000
Other assets
Investments in joint ventures	20,000,000	37,500,000
Deposits for real-estate leases	11,800,000	10,300,000
Other	41,300,000	37,300,000
Total other assets	142,200,000	112,100,000
Indemnification assets related to acquisitions	25,700,000	27,000,000
Fixed maturity and other open ended mutual funds	43,400,000	0
Accounts payable and accrued liabilities
Salaries and benefits	70,500,000	77,100,000
Incentive compensation	114,400,000	135,900,000
Customer credits, advanced payments and advanced billings	19,900,000	21,700,000
Dividends	4,900,000	65,500,000
Professional service fees	47,700,000	32,900,000
Interest accrued on debt	14,800,000	36,300,000
Accounts payable	17,600,000	16,400,000
Income taxes	22,100,000	47,500,000
Pension and other post retirement employee benefits	7,100,000	7,000,000
Other	79,800,000	71,000,000
Total accounts payable and accrued liabilities	420,200,000	538,900,000
Self-insurance reserves	19,100,000	27,600,000	55,800,000
Profit Sharing Contribution	2,300,000	0
Other liabilities
Pension and other post retirement employee benefits	166,100,000	164,000,000
Deferred rent-non-current portion	106,200,000	106,300,000
Interest accrued on UTPs	18,100,000	18,000,000
Legacy and other tax matters	8,600,000	15,400,000
Other	49,000,000	56,500,000
Total other liabilities	$ 348,000,000	$ 360,200,000