Dispositions (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended					12 Months Ended
	Oct. 07, 2015	Jan. 31, 2015	Dec. 31, 2015		Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2015		Dec. 31, 2014	Dec. 31, 2013	Oct. 01, 2015	Sep. 30, 2015	Sep. 09, 2015	Dec. 31, 2012
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Proceeds from sale of subsidiary	$ 19,600
Total assets for divested legal entities													$ 83,004
Amount of investments, cash, and cash equivalents held for sale													35,920
Amount of premiums and accounts receivable held for sale													17,312
Amount of property and equipment held for sale													19,368
Amount of other intangible assets held for sale													8,674
Amount of total liabilities held for sale													14,923
Amount of accounts payable and other liabilities held for sale													$ 13,622
Gain (loss) associated with divested business							$ 19,400	$ 1,121		$ (21,526)	$ 0
Total assets			$ 30,043,128	[1]			31,562,466	30,043,128	[1]	31,562,466	29,714,689
Fixed maturity securities, fair value			10,215,328				11,263,174	10,215,328		11,263,174
Cash and cash equivalents			1,288,305				1,318,656	1,288,305		1,318,656	1,717,184				$ 909,404
Premiums and accounts receivable			1,260,717				1,445,630	1,260,717		1,445,630
Reinsurance recoverables			7,470,403				7,254,585	7,470,403		7,254,585
Deferred acquisition costs			3,150,934				2,957,740	3,150,934		2,957,740	$ 3,128,931				$ 2,861,163
Total liabilities			25,519,161				26,381,159	25,519,161		26,381,159
Unearned premiums			6,423,720				6,529,675	6,423,720		6,529,675
Claims and benefits payable			3,896,719				3,698,606	3,896,719		3,698,606
Funds held under reinsurance			94,417				75,161	94,417		75,161
Other Income [Member]
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Gain on sale of assets			16,773
Assurant Health Supplemental and Small-Group Self-Funded Line of Business
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Cash consideration for line of business sold												$ 14,000
Gain on sale of disposal related to line of business												$ 5,336
Assurant Health Supplemental and Small-Group Self-Funded Line of Business | Selling, General and Administrative Expenses
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Loss on disposition of supplemental business			$ 11,587
Employee Benefits Business
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Cash consideration for line of business sold														$ 940,000
American Reliable Insurance Company
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Proceeds from sale of subsidiary		$ 117,860
Gain (loss) associated with divested business										(21,526)
Total assets							441,942			441,942
Fixed maturity securities, fair value							199,097			199,097
Cash and cash equivalents							48,695			48,695
Premiums and accounts receivable							26,186			26,186
Reinsurance recoverables							105,603			105,603
Deferred acquisition costs							25,055			25,055
Total liabilities							321,820			321,820
Unearned premiums							172,235			172,235
Claims and benefits payable							72,645			72,645
Funds held under reinsurance							$ 54,949			54,949
American Reliable Insurance Company | Selling, General and Administrative Expenses
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Gain (loss) associated with divested business					$ (4,164)	$ 5,284		$ 1,120		(21,526)
American Reliable Insurance Company | Goodwill | Underwriting, General and Administrative Expenses
Disposal Group, Not Discontinued Operation, Disposal Disclosures [Abstract]
Gain (loss) associated with divested business										$ (15,451)

[1] As of December 31, 2014, all goodwill on Assurant's balance sheet was held in the Corporate & Other segment. Beginning January 1, 2015, goodwill is included on the respective segment balance sheets.